** DISPUTED ** Py throughout 1.11.0 allows remote attackers to conduct a ReDoS (Regular expression Denial of Service) attack via a Subversion repository with crafted info data because the InfoSvnCommand argument is mishandled.
https://github.com/pytest-dev/py/issues/287

Py 1.10.0 includes a fix for CVE-2020-29651: A denial of service via regular expression in the py.path.svnwc component of py (aka python-py) through 1.9.0 could be used by attackers to cause a compute-time denial of service attack by supplying malicious input to the blame functionality.

Affected versions of Idna are vulnerable to Denial Of Service via the idna.encode(), where a specially crafted argument could lead to significant resource consumption. In version 3.7, this function has been updated to reject such inputs efficiently, minimizing resource use. A practical workaround involves enforcing a maximum domain name length of 253 characters before encoding, as the vulnerability is triggered by unusually large inputs that normal operations wouldn't encounter.

** DISPUTED ** Py throughout 1.11.0 allows remote attackers to conduct a ReDoS (Regular expression Denial of Service) attack via a Subversion repository with crafted info data because the InfoSvnCommand argument is mishandled.
https://github.com/pytest-dev/py/issues/287

Py 1.10.0 includes a fix for CVE-2020-29651: A denial of service via regular expression in the py.path.svnwc component of py (aka python-py) through 1.9.0 could be used by attackers to cause a compute-time denial of service attack by supplying malicious input to the blame functionality.

An issue was discovered in Django 2.2 before 2.2.13 and 3.0 before 3.0.7. Query parameters generated by the Django admin ForeignKeyRawIdWidget were not properly URL encoded, leading to a possibility of an XSS attack.

Affected versions of the Django package are vulnerable to SQL Injection due to improper handling of control characters in column aliases within FilteredRelation. The FilteredRelation class fails to properly sanitize column aliases containing control characters when used with QuerySet methods annotate(), aggregate(), extra(), values(), values_list(), and alias() via dictionary expansion (**kwargs).

Affected versions of the Django package are vulnerable to SQL Injection due to improper sanitization of band index parameters in PostGIS raster lookups. The raster lookup functionality in Django's GIS module fails to properly validate or escape untrusted data used as a band index when performing spatial queries against PostGIS databases.

Affected versions of Django are vulnerable to potential denial-of-service in intcomma template filter when used with very long strings.

A potential denial-of-service vulnerability has been identified in Django's urlize() and urlizetrunc() functions in django.utils.html. This vulnerability can be triggered by inputting huge strings containing a specific sequence of characters.

Django 3.2.14 and 4.0.6 include a fix for CVE-2022-34265: Potential SQL injection via Trunc(kind) and Extract(lookup_name) arguments.
https://www.djangoproject.com/weblog/2022/jul/04/security-releases

An issue was discovered in Django 2.2 before 2.2.13 and 3.0 before 3.0.7. In cases where a memcached backend does not perform key validation, passing malformed cache keys could result in a key collision, and potential data leakage.

Django 4.1.7, 4.0.10 and 3.2.18 include a fix for CVE-2023-24580: Potential denial-of-service vulnerability in file uploads.
https://www.djangoproject.com/weblog/2023/feb/14/security-releases

An issue was discovered in Django 2.2 before 2.2.16, 3.0 before 3.0.10, and 3.1 before 3.1.1 (when Python 3.7+ is used). The intermediate-level directories of the filesystem cache had the system's standard umask rather than 0o077.

Django versions 3.2.2, 3.1.10 and 2.2.22 include a fix for CVE-2021-32052: In Django 2.2 before 2.2.22, 3.1 before 3.1.10, and 3.2 before 3.2.2 (with Python 3.9.5+), URLValidator does not prohibit newlines and tabs (unless the URLField form field is used). If an application uses values with newlines in an HTTP response, header injection can occur. Django itself is unaffected because HttpResponse prohibits newlines in HTTP headers.
https://www.djangoproject.com/weblog/2021/may/06/security-releases

Affected versions of the Django package are vulnerable to Path Traversal due to improper validation of file paths in the django.contrib.admindocs module. The `TemplateDetailView` view allows staff members to verify the existence of arbitrary files by manipulating the file path. An attacker with staff privileges can exploit this vulnerability to check for the presence of files outside the template root directories, and if the `admindocs` templates are customized to display file contents, they can also access the contents of these files.

Django addresses a memory exhaustion issue in django.utils.numberformat.floatformat(). When floatformat receives a string representation of a number in scientific notation with a large exponent, it could lead to excessive memory consumption. To prevent this, decimals with more than 200 digits are now returned as-is.

Django 2.2.24, 3.1.12, and 3.2.4 include a fix for CVE-2021-33571: In Django 2.2 before 2.2.24, 3.x before 3.1.12, and 3.2 before 3.2.4, URLValidator, validate_ipv4_address, and validate_ipv46_address do not prohibit leading zero characters in octal literals. This may allow a bypass of access control that is based on IP addresses. (validate_ipv4_address and validate_ipv46_address are unaffected with Python 3.9.5+).
https://www.djangoproject.com/weblog/2021/jun/02/security-releases

Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to inefficient string concatenation when processing duplicate HTTP headers in ASGI mode. The ASGIRequest class combines repeated headers using repeated string concatenation, resulting in super-linear (quadratic) time complexity when processing requests with many duplicate headers.

Affected versions of the Django package are vulnerable to SQL Injection due to improper handling of column aliases containing periods in QuerySet.order_by() when combined with FilteredRelation. The QuerySet.order_by() method fails to properly sanitize column aliases that contain periods when the same alias is used in FilteredRelation via dictionary expansion. 
https://github.com/django/django/commit/90f5b10784ba5bf369caed87640e2b4394ea3314

Django 2.2.21, 3.1.9 and 3.2.1 include a fix for CVE-2021-31542: MultiPartParser, UploadedFile, and FieldFile allowed directory traversal via uploaded files with suitably crafted file names.
https://www.djangoproject.com/weblog/2021/may/04/security-releases

An issue was discovered in Django 4.2 before 4.2.21, 5.1 before 5.1.9, and 5.2 before 5.2.1. The django.utils.html.strip_tags() function is vulnerable to a potential denial-of-service (slow performance) when processing inputs containing large sequences of incomplete HTML tags. The template filter striptags is also vulnerable, because it is built on top of strip_tags().

In Django 3.2 before 3.2.16, 4.0 before 4.0.8, and 4.1 before 4.1.2, internationalized URLs were subject to a potential denial of service attack via the locale parameter, which is treated as a regular expression.

Affected versions of Django are vulnerable to potential Denial of Service via certain inputs with a very large number of Unicode characters in django.utils.encoding.uri_to_iri().

Django 1.11.29, 2.2.11 and 3.0.4 includes a fix for CVE-2020-9402: Django 1.11 before 1.11.29, 2.2 before 2.2.11, and 3.0 before 3.0.4 allows SQL Injection if untrusted data is used as a tolerance parameter in GIS functions and aggregates on Oracle. By passing a suitably crafted tolerance to GIS functions and aggregates on Oracle, it was possible to break escaping and inject malicious SQL.
https://www.djangoproject.com/weblog/2020/mar/04/security-releases

Django affected versions are vulnerable to a potential SQL injection in the HasKey(lhs, rhs) lookup on Oracle databases. The vulnerability arises when untrusted data is directly used as the lhs value in the django.db.models.fields.json.HasKey lookup. However, applications using the jsonfield.has_key lookup with the __ syntax remain unaffected by this issue.

Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to quadratic time complexity during HTML parsing in text truncation methods. The django.utils.text.Truncator.chars() and Truncator.words() methods (with html=True), as well as the truncatechars_html and truncatewords_html template filters, exhibit quadratic time complexity when processing inputs containing a large number of unmatched HTML end tags.

Django versions 2.2.25, 3.1.14 and 3.2.10 include a fix for CVE-2021-44420: In Django 2.2 before 2.2.25, 3.1 before 3.1.14, and 3.2 before 3.2.10, HTTP requests for URLs with trailing newlines could bypass upstream access control based on URL paths.
https://www.djangoproject.com/weblog/2021/dec/07/security-releases/

Django 2.1.15 and 2.2.8 includes a fix for CVE-2019-19118: A Django model admin displaying inline related models, where the user has view-only permissions to a parent model but edit permissions to the inline model, would be presented with an editing UI, allowing POST requests, for updating the inline model. Directly editing the view-only parent model was not possible, but the parent model's save() method was called, triggering potential side effects, and causing pre and post-save signal handlers to be invoked. To resolve this, the Django admin is adjusted to require edit permissions on the parent model in order for inline models to be editable.

Django 1.11.27, 2.2.9 and 3.0.1 include a fix for CVE-2019-19844: Account takeover. A suitably crafted email address (that is equal to an existing user's email address after case transformation of Unicode characters) would allow an attacker to be sent a password reset token for the matched user account. One mitigation in the new releases is to send password reset tokens only to the registered user email address.

Django has a potential denial-of-service vulnerability in django.utils.html.urlize() and AdminURLFieldWidget. The urlize and urlizetrunc functions, along with AdminURLFieldWidget, are vulnerable to denial-of-service attacks when handling inputs with a very large number of Unicode characters.

Affected versions of Django are potentially vulnerable to denial-of-service via the get_supported_language_variant() method. This method was susceptible to a denial-of-service attack when used with very long strings containing specific characters. Exploiting this vulnerability could cause significant delays or crashes in the affected application, potentially leading to service disruption.

Django versions 2.2.19, 3.0.13 and 3.1.7 include a fix for CVE-2021-23336: Web cache poisoning via 'django.utils.http.limited_parse_qsl()'. Django contains a copy of 'urllib.parse.parse_qsl' which was added to backport some security fixes. A further security fix has been issued recently such that 'parse_qsl(' no longer allows using ';' as a query parameter separator by default.

Django 4.2.1, 4.1.9 and 3.2.19 include a fix for CVE-2023-31047: In Django 3.2 before 3.2.19, 4.x before 4.1.9, and 4.2 before 4.2.1, it was possible to bypass validation when using one form field to upload multiple files. This multiple upload has never been supported by forms.FileField or forms.ImageField (only the last uploaded file was validated). However, Django's "Uploading multiple files" documentation suggested otherwise.
https://www.djangoproject.com/weblog/2023/may/03/security-releases

Affected versions of Django are vulnerable to potential regular expression denial-of-service (REDoS). django.utils.text.Truncator.words() method (with html=True) and truncatewords_html template filter were subject to a potential regular expression denial-of-service attack using a suitably crafted string (follow up to CVE-2019-14232 and CVE-2023-43665).

Affected versions of Django are vulnerable to a potential ReDoS (regular expression denial of service) in EmailValidator and URLValidator via a very large number of domain name labels of emails and URLs.

Django 2.2.27, 3.2.12 and 4.0.2 include a fix for CVE-2022-23833: Denial-of-service possibility in file uploads.
https://www.djangoproject.com/weblog/2022/feb/01/security-releases

Django 2.2.28, 3.2.13 and 4.0.4 include a fix for CVE-2022-28346: An issue was discovered in Django 2.2 before 2.2.28, 3.2 before 3.2.13, and 4.0 before 4.0.4. QuerySet.annotate(), aggregate(), and extra() methods are subject to SQL injection in column aliases via a crafted dictionary (with dictionary expansion) as the passed **kwargs.
https://www.djangoproject.com/weblog/2022/apr/11/security-releases

In Django 2.2 before 2.2.20, 3.0 before 3.0.14, and 3.1 before 3.1.8, MultiPartParser allowed directory traversal via uploaded files with suitably crafted file names. Built-in upload handlers were not affected by this vulnerability.

CVE-2025-64458: Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to slow Unicode NFKC normalization on Windows being applied to untrusted inputs. The django.contrib.auth.views.LoginView and django.contrib.auth.views.LogoutView, and django.views.i18n.set_language normalize user-controlled strings using Python’s NFKC algorithm, which is unusually slow on Windows for huge Unicode sequences and can be triggered to consume excessive CPU.

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45452: Storage.save in Django 2.2 before 2.2.26, 3.2 before 3.2.11, and 4.0 before 4.0.1 allows directory traversal if crafted filenames are directly passed to it.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases/

Affected versions of Django are vulnerable to a potential denial-of-service (DoS) attack in the `django.utils.html.strip_tags()` method. The vulnerability occurs when the `strip_tags()` method or the `striptags` template filter processes inputs containing large sequences of nested, incomplete HTML entities.

Affected versions of the Django package are vulnerable to Information Disclosure (Timing Attack) due to non-constant-time comparison in the mod_wsgi authentication handler. The django.contrib.auth.handlers.modwsgi.check_password() function does not perform user existence checks in constant time, allowing response timing differences to reveal whether usernames exist.

The {% debug %} template tag in Django 2.2 before 2.2.27, 3.2 before 3.2.12, and 4.0 before 4.0.2 does not properly encode the current context. This may lead to XSS.

Django fixes a potential denial-of-service vulnerability in XML ``Deserializer``.

An issue was discovered in Django 5.2 before 5.2.3, 5.1 before 5.1.11, and 4.2 before 4.2.23. Internal HTTP response logging does not escape request.path, which allows remote attackers to potentially manipulate log output via crafted URLs. This may lead to log injection or forgery when logs are viewed in terminals or processed by external systems.

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45116: An issue was discovered in Django 2.2 before 2.2.26, 3.2 before 3.2.11, and 4.0 before 4.0.1. Due to leveraging the Django Template Language's variable resolution logic, the dictsort template filter was potentially vulnerable to information disclosure, or an unintended method call, if passed a suitably crafted key.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45115: UserAttributeSimilarityValidator incurred significant overhead in evaluating a submitted password that was artificially large in relation to the comparison values. In a situation where access to user registration was unrestricted, this provided a potential vector for a denial-of-service attack.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases/

Affected versions of Django are affected by a potential denial-of-service vulnerability in the django.utils.html.urlize() function. The urlize and urlizetrunc template filters were susceptible to a denial-of-service attack via certain inputs containing many brackets. An attacker could exploit this vulnerability to cause significant delays or crashes in the affected application.

Affected versions of Django are affected by a directory-traversal vulnerability in the Storage.save() method. Derived classes of the django.core.files.storage.Storage base class that overrides the generate_filename() method without replicating the file path validations existing in the parent class could allow for directory traversal via certain inputs when calling save(). This could enable an attacker to manipulate file paths and access unintended directories.

Django 1.11.28, 2.2.10 and 3.0.3 include a fix for CVE-2020-7471: SQL Injection if untrusted data is used as a StringAgg delimiter (e.g., in Django applications that offer downloads of data as a series of rows with a user-specified column delimiter). By passing a suitably crafted delimiter to a contrib.postgres.aggregates.StringAgg instance, it was possible to break escaping and inject malicious SQL.

Affected versions of Django has a potential SQL injection vulnerability in the QuerySet.values() and QuerySet.values_list() methods. When used on models with a JSONField, these methods are susceptible to SQL injection through column aliases if a crafted JSON object key is passed as an argument.

A security vulnerability has been discovered in certain versions of Django, affecting the password reset functionality. The PasswordResetForm class in django.contrib.auth.forms inadvertently allowed attackers to enumerate user email addresses by exploiting unhandled exceptions during the email sending process. This could be done by issuing password reset requests and observing the responses. Django has implemented a fix where these exceptions are now caught and logged using the django.contrib.auth logger, preventing potential information leakage through error responses.

Django 2.2.18, 3.0.12 and 3.1.6 include a fix for CVE-2021-3281: The django.utils.archive.extract method (used by "startapp --template" and "startproject --template") allows directory traversal via an archive with absolute paths or relative paths with dot segments.

Django 4.2.7, 4.1.13 and 3.2.23 include a fix for CVE-2023-46695: Potential denial of service vulnerability in UsernameField on Windows.
https://www.djangoproject.com/weblog/2023/nov/01/security-releases

Affected versions of Django are vulnerable to Denial-of-Service via django.utils.text.Truncator. The django.utils.text.Truncator chars() and words() methods (when used with html=True) are subject to a potential DoS (denial of service) attack via certain inputs with very long, potentially malformed HTML text. The chars() and words() methods are used to implement the truncatechars_html and truncatewords_html template filters, which are thus also vulnerable. NOTE: this issue exists because of an incomplete fix for CVE-2019-14232.

Affected versions of Django are affected by a username enumeration vulnerability caused by timing differences in the django.contrib.auth.backends.ModelBackend.authenticate() method. This method allowed remote attackers to enumerate users through a timing attack involving login requests for users with unusable passwords. The timing difference in the authentication process exposed whether a username was valid or not, potentially aiding attackers in gaining unauthorized access.

Django 2.2.28, 3.2.13 and 4.0.4 include a fix for CVE-2022-28347: A SQL injection issue was discovered in QuerySet.explain() in Django 2.2 before 2.2.28, 3.2 before 3.2.13, and 4.0 before 4.0.4. This occurs by passing a crafted dictionary (with dictionary expansion) as the **options argument, and placing the injection payload in an option name.
https://www.djangoproject.com/weblog/2022/apr/11/security-releases

Django 2.2.16, 3.0.10 and 3.1.1 include a fix for CVE-2020-24583: An issue was discovered in Django 2.2 before 2.2.16, 3.0 before 3.0.10, and 3.1 before 3.1.1 (when Python 3.7+ is used). FILE_UPLOAD_DIRECTORY_PERMISSIONS mode was not applied to intermediate-level directories created in the process of uploading files. It was also not applied to intermediate-level collected static directories when using the collectstatic management command.
#NOTE: This vulnerability affects only users of Python versions above 3.7.
https://www.djangoproject.com/weblog/2020/sep/01/security-releases

Django 3.2.17, 4.0.9 and 4.1.6 includes a fix for CVE-2023-23969: In Django 3.2 before 3.2.17, 4.0 before 4.0.9, and 4.1 before 4.1.6, the parsed values of Accept-Language headers are cached in order to avoid repetitive parsing. This leads to a potential denial-of-service vector via excessive memory usage if the raw value of Accept-Language headers is very large.
https://www.djangoproject.com/weblog/2023/feb/01/security-releases

Affected versions of the `django` package are vulnerable to Download of Code Without Integrity Check due to improper handling of user-supplied input in the HTTP FileResponse class. The vulnerability arises because the Content-Disposition header of a FileResponse can be set using a filename derived from user input without sufficient validation. An attacker can exploit this by crafting a request that causes a file with malicious content to be downloaded, potentially executing arbitrary code on the client system when the file is opened.

CVE-2025-64459: Affected versions of the Django package are vulnerable to SQL Injection due to improper input validation, allowing the internal _connector keyword argument to be accepted from untrusted dictionaries via expansion. The .filter(), .exclude(), and .get() methods on QuerySet, as well as the Q class, resolve **kwargs and will treat a supplied _connector value as the logical connector without constraining it to the expected set (AND/OR), permitting attacker-controlled tokens to influence SQL predicate construction.

Affected versions of the Django package are vulnerable to SQL Injection due to insufficient input sanitization in FilteredRelation column aliases. The FilteredRelation class fails to properly validate or escape column alias names when they are provided through dictionary expansion as keyword arguments to QuerySet.annotate() or QuerySet.alias() methods, allowing malicious SQL code to be injected directly into the generated database queries.

Django fixes potential SQL injection in ``FilteredRelation`` column aliases on PostgreSQL.

Affected versions of the sqlparse package are vulnerable to Denial of Service (DoS) due to missing hard limits on token grouping recursion depth and token processing when formatting very large SQL tuple lists. During sqlparse.format() processing, the sqlparse.engine.grouping._group_matching() and sqlparse.engine.grouping._group() functions can recurse and iterate over excessively large tlist.tokens without enforcing MAX_GROUPING_DEPTH or MAX_GROUPING_TOKENS, allowing grouping work to grow until it effectively hangs.

Affected versions of this package are vulnerable to Denial of Service (DoS) attacks due to Algorithmic Complexity. The SQL parser fails to enforce limits when processing deeply nested tuples and large token sequences, leading to excessive resource consumption through crafted SQL statements with extreme nesting depth or token counts.

**Note:** This issue is due to an incomplete fix for CVE-2024-4340.

Sqlparse 0.5.0 addresses a potential denial of service (DoS) vulnerability related to recursion errors in deeply nested SQL statements. To mitigate this issue, the update replaces recursion errors with a general SQLParseError, improving the resilience and stability of the parsing process.

Sqlparse 0.4.4 includes a fix for CVE-2023-30608: Parser contains a regular expression that is vulnerable to ReDOS (Regular Expression Denial of Service).
https://github.com/andialbrecht/sqlparse/security/advisories/GHSA-rrm6-wvj7-cwh2

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to redirect handling that drains connections by decompressing redirect response bodies without enforcing streaming read limits. The issue occurs when using urllib3’s streaming mode (for example, preload_content=False) while allowing redirects, because urllib3.response.HTTPResponse.drain_conn() would call HTTPResponse.read() in a way that decoded/decompressed the entire redirect response body even before any streaming reads were performed, effectively bypassing decompression-bomb safeguards.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to improper handling of highly compressed HTTP response bodies during streaming decompression. The urllib3.HTTPResponse methods stream(), read(), read1(), read_chunked(), and readinto() may fully decompress a minimal but highly compressed payload based on the Content-Encoding header into an internal buffer instead of limiting the decompressed output to the requested chunk size, causing excessive CPU usage and massive memory allocation on the client side.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to allowing an unbounded number of content-encoding decompression steps for HTTP responses. The HTTPResponse content decoding pipeline in urllib3 follows the Content-Encoding header and applies each advertised compression algorithm in sequence without enforcing a maximum chain length or effective output size, so a malicious peer can send a response with a very long encoding chain that triggers excessive CPU use and massive memory allocation during decompression.

Urllib3's ProxyManager ensures that the Proxy-Authorization header is correctly directed only to configured proxies. However, when HTTP requests bypass urllib3's proxy support, there's a risk of inadvertently setting the Proxy-Authorization header, which remains ineffective without a forwarding or tunneling proxy. Urllib3 does not recognize this header as carrying authentication data, failing to remove it during cross-origin redirects. While this scenario is uncommon and poses low risk to most users, urllib3 now proactively removes the Proxy-Authorization header during cross-origin redirects as a precautionary measure. Users are advised to utilize urllib3's proxy support or disable automatic redirects to handle the Proxy-Authorization header securely. Despite these precautions, urllib3 defaults to stripping the header to safeguard users who may inadvertently misconfigure requests.

Urllib3 1.26.17 and 2.0.5 include a fix for CVE-2023-43804: Urllib3 doesn't treat the 'Cookie' HTTP header special or provide any helpers for managing cookies over HTTP, that is the responsibility of the user. However, it is possible for a user to specify a 'Cookie' header and unknowingly leak information via HTTP redirects to a different origin if that user doesn't disable redirects explicitly.
https://github.com/urllib3/urllib3/security/advisories/GHSA-v845-jxx5-vc9f

Urllib3 1.26.5 includes a fix for CVE-2021-33503: When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking, causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redirect.
https://github.com/advisories/GHSA-q2q7-5pp4-w6pg

The _encode_invalid_chars function in util/url.py in the urllib3 library 1.25.2 through 1.25.7 for Python allows a denial of service (CPU consumption) because of an inefficient algorithm. The percent_encodings array contains all matches of percent encodings. It is not deduplicated. For a URL of length N, the size of percent_encodings may be up to O(N). The next step (normalize existing percent-encoded bytes) also takes up to O(N) for each step, so the total time is O(N^2). If percent_encodings were deduplicated, the time to compute _encode_invalid_chars would be O(kN), where k is at most 484 ((10+6*2)^2). See: CVE-2020-7212.

Affected versions of urllib3 are vulnerable to an HTTP redirect handling vulnerability that fails to remove the HTTP request body when a POST changes to a GET via 301, 302, or 303 responses. This flaw can expose sensitive request data if the origin service is compromised and redirects to a malicious endpoint, though exploitability is low when no sensitive data is used. The vulnerability affects automatic redirect behavior. It is fixed in versions 1.26.18 and 2.0.7; update or disable redirects using redirects=False.
This vulnerability is specific to Python's urllib3 library.

urllib3 is a user-friendly HTTP client library for Python. Prior to 2.5.0, it is possible to disable redirects for all requests by instantiating a PoolManager and specifying retries in a way that disable redirects. By default, requests and botocore users are not affected. An application attempting to mitigate SSRF or open redirect vulnerabilities by disabling redirects at the PoolManager level will remain vulnerable. This issue has been patched in version 2.5.0.

Urllib3 1.25.9 includes a fix for CVE-2020-26137: Urllib3 before 1.25.9 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserting CR and LF control characters in the first argument of putrequest(). NOTE: this is similar to CVE-2020-26116.
https://github.com/python/cpython/issues/83784
https://github.com/urllib3/urllib3/pull/1800

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to redirect handling that drains connections by decompressing redirect response bodies without enforcing streaming read limits. The issue occurs when using urllib3’s streaming mode (for example, preload_content=False) while allowing redirects, because urllib3.response.HTTPResponse.drain_conn() would call HTTPResponse.read() in a way that decoded/decompressed the entire redirect response body even before any streaming reads were performed, effectively bypassing decompression-bomb safeguards.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to improper handling of highly compressed HTTP response bodies during streaming decompression. The urllib3.HTTPResponse methods stream(), read(), read1(), read_chunked(), and readinto() may fully decompress a minimal but highly compressed payload based on the Content-Encoding header into an internal buffer instead of limiting the decompressed output to the requested chunk size, causing excessive CPU usage and massive memory allocation on the client side.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to allowing an unbounded number of content-encoding decompression steps for HTTP responses. The HTTPResponse content decoding pipeline in urllib3 follows the Content-Encoding header and applies each advertised compression algorithm in sequence without enforcing a maximum chain length or effective output size, so a malicious peer can send a response with a very long encoding chain that triggers excessive CPU use and massive memory allocation during decompression.

Urllib3's ProxyManager ensures that the Proxy-Authorization header is correctly directed only to configured proxies. However, when HTTP requests bypass urllib3's proxy support, there's a risk of inadvertently setting the Proxy-Authorization header, which remains ineffective without a forwarding or tunneling proxy. Urllib3 does not recognize this header as carrying authentication data, failing to remove it during cross-origin redirects. While this scenario is uncommon and poses low risk to most users, urllib3 now proactively removes the Proxy-Authorization header during cross-origin redirects as a precautionary measure. Users are advised to utilize urllib3's proxy support or disable automatic redirects to handle the Proxy-Authorization header securely. Despite these precautions, urllib3 defaults to stripping the header to safeguard users who may inadvertently misconfigure requests.

Urllib3 1.26.17 and 2.0.5 include a fix for CVE-2023-43804: Urllib3 doesn't treat the 'Cookie' HTTP header special or provide any helpers for managing cookies over HTTP, that is the responsibility of the user. However, it is possible for a user to specify a 'Cookie' header and unknowingly leak information via HTTP redirects to a different origin if that user doesn't disable redirects explicitly.
https://github.com/urllib3/urllib3/security/advisories/GHSA-v845-jxx5-vc9f

Urllib3 1.26.5 includes a fix for CVE-2021-33503: When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking, causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redirect.
https://github.com/advisories/GHSA-q2q7-5pp4-w6pg

The _encode_invalid_chars function in util/url.py in the urllib3 library 1.25.2 through 1.25.7 for Python allows a denial of service (CPU consumption) because of an inefficient algorithm. The percent_encodings array contains all matches of percent encodings. It is not deduplicated. For a URL of length N, the size of percent_encodings may be up to O(N). The next step (normalize existing percent-encoded bytes) also takes up to O(N) for each step, so the total time is O(N^2). If percent_encodings were deduplicated, the time to compute _encode_invalid_chars would be O(kN), where k is at most 484 ((10+6*2)^2). See: CVE-2020-7212.

Affected versions of urllib3 are vulnerable to an HTTP redirect handling vulnerability that fails to remove the HTTP request body when a POST changes to a GET via 301, 302, or 303 responses. This flaw can expose sensitive request data if the origin service is compromised and redirects to a malicious endpoint, though exploitability is low when no sensitive data is used. The vulnerability affects automatic redirect behavior. It is fixed in versions 1.26.18 and 2.0.7; update or disable redirects using redirects=False.
This vulnerability is specific to Python's urllib3 library.

urllib3 is a user-friendly HTTP client library for Python. Prior to 2.5.0, it is possible to disable redirects for all requests by instantiating a PoolManager and specifying retries in a way that disable redirects. By default, requests and botocore users are not affected. An application attempting to mitigate SSRF or open redirect vulnerabilities by disabling redirects at the PoolManager level will remain vulnerable. This issue has been patched in version 2.5.0.

Urllib3 1.25.9 includes a fix for CVE-2020-26137: Urllib3 before 1.25.9 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserting CR and LF control characters in the first argument of putrequest(). NOTE: this is similar to CVE-2020-26116.
https://github.com/python/cpython/issues/83784
https://github.com/urllib3/urllib3/pull/1800

Affected versions of the gunicorn package are vulnerable to HTTP Request/Response Smuggling due to improper validation of the Transfer-Encoding header that enables a TE.CL desynchronisation condition. Gunicorn’s HTTP parser does not consistently enforce RFC semantics when parsing conflicting or unsupported request framing—such as messages containing both Transfer-Encoding and Content-Length—so the backend may fall back to Content-Length while an intermediary treats the message as chunked.

Gunicorn 20.0.1 fixes chunked encoding support to prevent http request smuggling attacks.
https://github.com/benoitc/gunicorn/issues/2176
https://github.com/p4k03n4t0r/http-request-smuggling#request-smuggling-using-mitmproxy-and-gunicorn

Gunicorn fails to properly validate Transfer-Encoding headers, leading to HTTP Request Smuggling (HRS) vulnerabilities. By crafting requests with conflicting Transfer-Encoding headers, attackers can bypass security restrictions and access restricted endpoints. This issue is due to Gunicorn's handling of Transfer-Encoding headers, where it incorrectly processes requests with multiple, conflicting Transfer-Encoding headers, treating them as chunked regardless of the final encoding specified. This vulnerability allows for a range of attacks including cache poisoning, session manipulation, and data exposure.

Requests is an HTTP library. Due to a URL parsing issue, Requests releases prior to 2.32.4 may leak .netrc credentials to third parties for specific maliciously-crafted URLs. Users should upgrade to version 2.32.4 to receive a fix. For older versions of Requests, use of the .netrc file can be disabled with `trust_env=False` on one's Requests Session.

Affected versions of Requests are vulnerable to proxy credential leakage. When redirected to an HTTPS endpoint, the Proxy-Authorization header is forwarded to the destination server due to the use of rebuild_proxies to reattach the header. This may allow a malicious actor to exfiltrate sensitive information.

Affected versions of the requests package are vulnerable to Insecure Temporary File reuse due to predictable temporary filename generation in extract_zipped_paths(). The requests.utils.extract_zipped_paths() utility extracts files from zip archives into the system temporary directory using a deterministic path, and if that file already exists, the function reuses it without validating that it is the expected extracted content.

Affected versions of Requests, when making requests through a Requests `Session`, if the first request is made with `verify=False` to disable cert verification, all subsequent requests to the same host will continue to ignore cert verification regardless of changes to the value of `verify`. This behavior will continue for the lifecycle of the connection in the connection pool. Requests 2.32.0 fixes the issue, but versions 2.32.0 and 2.32.1 were yanked due to conflicts with CVE-2024-35195 mitigation.

Certifi 2022.12.07 includes a fix for CVE-2022-23491: Certifi 2022.12.07 removes root certificates from "TrustCor" from the root store. These are in the process of being removed from Mozilla's trust store. TrustCor's root certificates are being removed pursuant to an investigation prompted by media reporting that TrustCor's ownership also operated a business that produced spyware. Conclusions of Mozilla's investigation can be found in the linked google group discussion.

Certifi 2023.07.22 includes a fix for CVE-2023-37920: Certifi prior to version 2023.07.22 recognizes "e-Tugra" root certificates. e-Tugra's root certificates were subject to an investigation prompted by reporting of security issues in their systems. Certifi 2023.07.22 removes root certificates from "e-Tugra" from the root store.
https://github.com/certifi/python-certifi/security/advisories/GHSA-xqr8-7jwr-rhp7

Certifi 2022.12.07 includes a fix for CVE-2022-23491: Certifi 2022.12.07 removes root certificates from "TrustCor" from the root store. These are in the process of being removed from Mozilla's trust store. TrustCor's root certificates are being removed pursuant to an investigation prompted by media reporting that TrustCor's ownership also operated a business that produced spyware. Conclusions of Mozilla's investigation can be found in the linked google group discussion.

Certifi 2023.07.22 includes a fix for CVE-2023-37920: Certifi prior to version 2023.07.22 recognizes "e-Tugra" root certificates. e-Tugra's root certificates were subject to an investigation prompted by reporting of security issues in their systems. Certifi 2023.07.22 removes root certificates from "e-Tugra" from the root store.
https://github.com/certifi/python-certifi/security/advisories/GHSA-xqr8-7jwr-rhp7

Affected versions of Sentry's Python SDK are vulnerable to unintentional exposure of environment variables to subprocesses despite the env={} setting. In Python's 'subprocess' calls, all environment variables are passed to subprocesses by default. However, if you specifically do not want them to be passed to subprocesses, you may use 'env' argument in 'subprocess' calls. Due to the bug in Sentry SDK, with the Stdlib integration enabled (which is enabled by default), this expectation is not fulfilled, and all environment variables are being passed to subprocesses instead. 
As a workaround, and if passing environment variables to child processes poses a security risk for you, you can disable all default integrations.

Sentry-sdk 1.14.0 includes a fix for CVE-2023-28117: When using the Django integration of versions prior to 1.14.0 of the Sentry SDK in a specific configuration it is possible to leak sensitive cookies values, including the session cookie to Sentry. These sensitive cookies could then be used by someone with access to your Sentry issues to impersonate or escalate their privileges within your application. In order for these sensitive values to be leaked, the Sentry SDK configuration must have 'sendDefaultPII' set to 'True'; one must use a custom name for either 'SESSION_COOKIE_NAME' or 'CSRF_COOKIE_NAME' in one's Django settings; and one must not be configured in one's organization or project settings to use Sentry's data scrubbing features to account for the custom cookie names. As of version 1.14.0, the Django integration of the 'sentry-sdk' will detect the custom cookie names based on one's Django settings and will remove the values from the payload before sending the data to Sentry. As a workaround, use the SDK's filtering mechanism to remove the cookies from the payload that is sent to Sentry. For error events, this can be done with the 'before_send' callback method and for performance related events (transactions) one can use the 'before_send_transaction' callback method. Those who want to handle filtering of these values on the server-side can also use Sentry's advanced data scrubbing feature to account for the custom cookie names. Look for the '$http.cookies', '$http.headers', '$request.cookies', or '$request.headers' fields to target with a scrubbing rule.
https://github.com/getsentry/sentry-python/security/advisories/GHSA-29pr-6jr8-q5jm

Sentry-sdk 1.4.1 includes a fix for a Race Condition vulnerability.
https://github.com/getsentry/sentry-python/pull/1203

A SQL Injection issue in the SQL Panel in Jazzband Django Debug Toolbar before 1.11.1, 2.x before 2.2.1, and 3.x before 3.2.1 allows attackers to execute SQL statements by changing the raw_sql input field of the SQL explain, analyze, or select form. See CVE-2021-30459.

** DISPUTED ** Py throughout 1.11.0 allows remote attackers to conduct a ReDoS (Regular expression Denial of Service) attack via a Subversion repository with crafted info data because the InfoSvnCommand argument is mishandled.
https://github.com/pytest-dev/py/issues/287

Py 1.10.0 includes a fix for CVE-2020-29651: A denial of service via regular expression in the py.path.svnwc component of py (aka python-py) through 1.9.0 could be used by attackers to cause a compute-time denial of service attack by supplying malicious input to the blame functionality.

Affected versions of Idna are vulnerable to Denial Of Service via the idna.encode(), where a specially crafted argument could lead to significant resource consumption. In version 3.7, this function has been updated to reject such inputs efficiently, minimizing resource use. A practical workaround involves enforcing a maximum domain name length of 253 characters before encoding, as the vulnerability is triggered by unusually large inputs that normal operations wouldn't encounter.

** DISPUTED ** Py throughout 1.11.0 allows remote attackers to conduct a ReDoS (Regular expression Denial of Service) attack via a Subversion repository with crafted info data because the InfoSvnCommand argument is mishandled.
https://github.com/pytest-dev/py/issues/287

Py 1.10.0 includes a fix for CVE-2020-29651: A denial of service via regular expression in the py.path.svnwc component of py (aka python-py) through 1.9.0 could be used by attackers to cause a compute-time denial of service attack by supplying malicious input to the blame functionality.

An issue was discovered in Django 2.2 before 2.2.13 and 3.0 before 3.0.7. Query parameters generated by the Django admin ForeignKeyRawIdWidget were not properly URL encoded, leading to a possibility of an XSS attack.

Affected versions of the Django package are vulnerable to SQL Injection due to improper handling of control characters in column aliases within FilteredRelation. The FilteredRelation class fails to properly sanitize column aliases containing control characters when used with QuerySet methods annotate(), aggregate(), extra(), values(), values_list(), and alias() via dictionary expansion (**kwargs).

Affected versions of the Django package are vulnerable to SQL Injection due to improper sanitization of band index parameters in PostGIS raster lookups. The raster lookup functionality in Django's GIS module fails to properly validate or escape untrusted data used as a band index when performing spatial queries against PostGIS databases.

Affected versions of Django are vulnerable to potential denial-of-service in intcomma template filter when used with very long strings.

A potential denial-of-service vulnerability has been identified in Django's urlize() and urlizetrunc() functions in django.utils.html. This vulnerability can be triggered by inputting huge strings containing a specific sequence of characters.

Django 3.2.14 and 4.0.6 include a fix for CVE-2022-34265: Potential SQL injection via Trunc(kind) and Extract(lookup_name) arguments.
https://www.djangoproject.com/weblog/2022/jul/04/security-releases

An issue was discovered in Django 2.2 before 2.2.13 and 3.0 before 3.0.7. In cases where a memcached backend does not perform key validation, passing malformed cache keys could result in a key collision, and potential data leakage.

Django 4.1.7, 4.0.10 and 3.2.18 include a fix for CVE-2023-24580: Potential denial-of-service vulnerability in file uploads.
https://www.djangoproject.com/weblog/2023/feb/14/security-releases

An issue was discovered in Django 2.2 before 2.2.16, 3.0 before 3.0.10, and 3.1 before 3.1.1 (when Python 3.7+ is used). The intermediate-level directories of the filesystem cache had the system's standard umask rather than 0o077.

Django versions 3.2.2, 3.1.10 and 2.2.22 include a fix for CVE-2021-32052: In Django 2.2 before 2.2.22, 3.1 before 3.1.10, and 3.2 before 3.2.2 (with Python 3.9.5+), URLValidator does not prohibit newlines and tabs (unless the URLField form field is used). If an application uses values with newlines in an HTTP response, header injection can occur. Django itself is unaffected because HttpResponse prohibits newlines in HTTP headers.
https://www.djangoproject.com/weblog/2021/may/06/security-releases

Affected versions of the Django package are vulnerable to Path Traversal due to improper validation of file paths in the django.contrib.admindocs module. The `TemplateDetailView` view allows staff members to verify the existence of arbitrary files by manipulating the file path. An attacker with staff privileges can exploit this vulnerability to check for the presence of files outside the template root directories, and if the `admindocs` templates are customized to display file contents, they can also access the contents of these files.

Django addresses a memory exhaustion issue in django.utils.numberformat.floatformat(). When floatformat receives a string representation of a number in scientific notation with a large exponent, it could lead to excessive memory consumption. To prevent this, decimals with more than 200 digits are now returned as-is.

Django 2.2.24, 3.1.12, and 3.2.4 include a fix for CVE-2021-33571: In Django 2.2 before 2.2.24, 3.x before 3.1.12, and 3.2 before 3.2.4, URLValidator, validate_ipv4_address, and validate_ipv46_address do not prohibit leading zero characters in octal literals. This may allow a bypass of access control that is based on IP addresses. (validate_ipv4_address and validate_ipv46_address are unaffected with Python 3.9.5+).
https://www.djangoproject.com/weblog/2021/jun/02/security-releases

Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to inefficient string concatenation when processing duplicate HTTP headers in ASGI mode. The ASGIRequest class combines repeated headers using repeated string concatenation, resulting in super-linear (quadratic) time complexity when processing requests with many duplicate headers.

Affected versions of the Django package are vulnerable to SQL Injection due to improper handling of column aliases containing periods in QuerySet.order_by() when combined with FilteredRelation. The QuerySet.order_by() method fails to properly sanitize column aliases that contain periods when the same alias is used in FilteredRelation via dictionary expansion. 
https://github.com/django/django/commit/90f5b10784ba5bf369caed87640e2b4394ea3314

Django 2.2.21, 3.1.9 and 3.2.1 include a fix for CVE-2021-31542: MultiPartParser, UploadedFile, and FieldFile allowed directory traversal via uploaded files with suitably crafted file names.
https://www.djangoproject.com/weblog/2021/may/04/security-releases

An issue was discovered in Django 4.2 before 4.2.21, 5.1 before 5.1.9, and 5.2 before 5.2.1. The django.utils.html.strip_tags() function is vulnerable to a potential denial-of-service (slow performance) when processing inputs containing large sequences of incomplete HTML tags. The template filter striptags is also vulnerable, because it is built on top of strip_tags().

In Django 3.2 before 3.2.16, 4.0 before 4.0.8, and 4.1 before 4.1.2, internationalized URLs were subject to a potential denial of service attack via the locale parameter, which is treated as a regular expression.

Affected versions of Django are vulnerable to potential Denial of Service via certain inputs with a very large number of Unicode characters in django.utils.encoding.uri_to_iri().

Django 1.11.29, 2.2.11 and 3.0.4 includes a fix for CVE-2020-9402: Django 1.11 before 1.11.29, 2.2 before 2.2.11, and 3.0 before 3.0.4 allows SQL Injection if untrusted data is used as a tolerance parameter in GIS functions and aggregates on Oracle. By passing a suitably crafted tolerance to GIS functions and aggregates on Oracle, it was possible to break escaping and inject malicious SQL.
https://www.djangoproject.com/weblog/2020/mar/04/security-releases

Django affected versions are vulnerable to a potential SQL injection in the HasKey(lhs, rhs) lookup on Oracle databases. The vulnerability arises when untrusted data is directly used as the lhs value in the django.db.models.fields.json.HasKey lookup. However, applications using the jsonfield.has_key lookup with the __ syntax remain unaffected by this issue.

Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to quadratic time complexity during HTML parsing in text truncation methods. The django.utils.text.Truncator.chars() and Truncator.words() methods (with html=True), as well as the truncatechars_html and truncatewords_html template filters, exhibit quadratic time complexity when processing inputs containing a large number of unmatched HTML end tags.

Django versions 2.2.25, 3.1.14 and 3.2.10 include a fix for CVE-2021-44420: In Django 2.2 before 2.2.25, 3.1 before 3.1.14, and 3.2 before 3.2.10, HTTP requests for URLs with trailing newlines could bypass upstream access control based on URL paths.
https://www.djangoproject.com/weblog/2021/dec/07/security-releases/

Django 2.1.15 and 2.2.8 includes a fix for CVE-2019-19118: A Django model admin displaying inline related models, where the user has view-only permissions to a parent model but edit permissions to the inline model, would be presented with an editing UI, allowing POST requests, for updating the inline model. Directly editing the view-only parent model was not possible, but the parent model's save() method was called, triggering potential side effects, and causing pre and post-save signal handlers to be invoked. To resolve this, the Django admin is adjusted to require edit permissions on the parent model in order for inline models to be editable.

Django 1.11.27, 2.2.9 and 3.0.1 include a fix for CVE-2019-19844: Account takeover. A suitably crafted email address (that is equal to an existing user's email address after case transformation of Unicode characters) would allow an attacker to be sent a password reset token for the matched user account. One mitigation in the new releases is to send password reset tokens only to the registered user email address.

Django has a potential denial-of-service vulnerability in django.utils.html.urlize() and AdminURLFieldWidget. The urlize and urlizetrunc functions, along with AdminURLFieldWidget, are vulnerable to denial-of-service attacks when handling inputs with a very large number of Unicode characters.

Affected versions of Django are potentially vulnerable to denial-of-service via the get_supported_language_variant() method. This method was susceptible to a denial-of-service attack when used with very long strings containing specific characters. Exploiting this vulnerability could cause significant delays or crashes in the affected application, potentially leading to service disruption.

Django versions 2.2.19, 3.0.13 and 3.1.7 include a fix for CVE-2021-23336: Web cache poisoning via 'django.utils.http.limited_parse_qsl()'. Django contains a copy of 'urllib.parse.parse_qsl' which was added to backport some security fixes. A further security fix has been issued recently such that 'parse_qsl(' no longer allows using ';' as a query parameter separator by default.

Django 4.2.1, 4.1.9 and 3.2.19 include a fix for CVE-2023-31047: In Django 3.2 before 3.2.19, 4.x before 4.1.9, and 4.2 before 4.2.1, it was possible to bypass validation when using one form field to upload multiple files. This multiple upload has never been supported by forms.FileField or forms.ImageField (only the last uploaded file was validated). However, Django's "Uploading multiple files" documentation suggested otherwise.
https://www.djangoproject.com/weblog/2023/may/03/security-releases

Affected versions of Django are vulnerable to potential regular expression denial-of-service (REDoS). django.utils.text.Truncator.words() method (with html=True) and truncatewords_html template filter were subject to a potential regular expression denial-of-service attack using a suitably crafted string (follow up to CVE-2019-14232 and CVE-2023-43665).

Affected versions of Django are vulnerable to a potential ReDoS (regular expression denial of service) in EmailValidator and URLValidator via a very large number of domain name labels of emails and URLs.

Django 2.2.27, 3.2.12 and 4.0.2 include a fix for CVE-2022-23833: Denial-of-service possibility in file uploads.
https://www.djangoproject.com/weblog/2022/feb/01/security-releases

Django 2.2.28, 3.2.13 and 4.0.4 include a fix for CVE-2022-28346: An issue was discovered in Django 2.2 before 2.2.28, 3.2 before 3.2.13, and 4.0 before 4.0.4. QuerySet.annotate(), aggregate(), and extra() methods are subject to SQL injection in column aliases via a crafted dictionary (with dictionary expansion) as the passed **kwargs.
https://www.djangoproject.com/weblog/2022/apr/11/security-releases

In Django 2.2 before 2.2.20, 3.0 before 3.0.14, and 3.1 before 3.1.8, MultiPartParser allowed directory traversal via uploaded files with suitably crafted file names. Built-in upload handlers were not affected by this vulnerability.

CVE-2025-64458: Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to slow Unicode NFKC normalization on Windows being applied to untrusted inputs. The django.contrib.auth.views.LoginView and django.contrib.auth.views.LogoutView, and django.views.i18n.set_language normalize user-controlled strings using Python’s NFKC algorithm, which is unusually slow on Windows for huge Unicode sequences and can be triggered to consume excessive CPU.

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45452: Storage.save in Django 2.2 before 2.2.26, 3.2 before 3.2.11, and 4.0 before 4.0.1 allows directory traversal if crafted filenames are directly passed to it.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases/

Affected versions of Django are vulnerable to a potential denial-of-service (DoS) attack in the `django.utils.html.strip_tags()` method. The vulnerability occurs when the `strip_tags()` method or the `striptags` template filter processes inputs containing large sequences of nested, incomplete HTML entities.

Affected versions of the Django package are vulnerable to Information Disclosure (Timing Attack) due to non-constant-time comparison in the mod_wsgi authentication handler. The django.contrib.auth.handlers.modwsgi.check_password() function does not perform user existence checks in constant time, allowing response timing differences to reveal whether usernames exist.

The {% debug %} template tag in Django 2.2 before 2.2.27, 3.2 before 3.2.12, and 4.0 before 4.0.2 does not properly encode the current context. This may lead to XSS.

Django fixes a potential denial-of-service vulnerability in XML ``Deserializer``.

An issue was discovered in Django 5.2 before 5.2.3, 5.1 before 5.1.11, and 4.2 before 4.2.23. Internal HTTP response logging does not escape request.path, which allows remote attackers to potentially manipulate log output via crafted URLs. This may lead to log injection or forgery when logs are viewed in terminals or processed by external systems.

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45116: An issue was discovered in Django 2.2 before 2.2.26, 3.2 before 3.2.11, and 4.0 before 4.0.1. Due to leveraging the Django Template Language's variable resolution logic, the dictsort template filter was potentially vulnerable to information disclosure, or an unintended method call, if passed a suitably crafted key.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45115: UserAttributeSimilarityValidator incurred significant overhead in evaluating a submitted password that was artificially large in relation to the comparison values. In a situation where access to user registration was unrestricted, this provided a potential vector for a denial-of-service attack.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases/

Affected versions of Django are affected by a potential denial-of-service vulnerability in the django.utils.html.urlize() function. The urlize and urlizetrunc template filters were susceptible to a denial-of-service attack via certain inputs containing many brackets. An attacker could exploit this vulnerability to cause significant delays or crashes in the affected application.

Affected versions of Django are affected by a directory-traversal vulnerability in the Storage.save() method. Derived classes of the django.core.files.storage.Storage base class that overrides the generate_filename() method without replicating the file path validations existing in the parent class could allow for directory traversal via certain inputs when calling save(). This could enable an attacker to manipulate file paths and access unintended directories.

Django 1.11.28, 2.2.10 and 3.0.3 include a fix for CVE-2020-7471: SQL Injection if untrusted data is used as a StringAgg delimiter (e.g., in Django applications that offer downloads of data as a series of rows with a user-specified column delimiter). By passing a suitably crafted delimiter to a contrib.postgres.aggregates.StringAgg instance, it was possible to break escaping and inject malicious SQL.

Affected versions of Django has a potential SQL injection vulnerability in the QuerySet.values() and QuerySet.values_list() methods. When used on models with a JSONField, these methods are susceptible to SQL injection through column aliases if a crafted JSON object key is passed as an argument.

A security vulnerability has been discovered in certain versions of Django, affecting the password reset functionality. The PasswordResetForm class in django.contrib.auth.forms inadvertently allowed attackers to enumerate user email addresses by exploiting unhandled exceptions during the email sending process. This could be done by issuing password reset requests and observing the responses. Django has implemented a fix where these exceptions are now caught and logged using the django.contrib.auth logger, preventing potential information leakage through error responses.

Django 2.2.18, 3.0.12 and 3.1.6 include a fix for CVE-2021-3281: The django.utils.archive.extract method (used by "startapp --template" and "startproject --template") allows directory traversal via an archive with absolute paths or relative paths with dot segments.

Django 4.2.7, 4.1.13 and 3.2.23 include a fix for CVE-2023-46695: Potential denial of service vulnerability in UsernameField on Windows.
https://www.djangoproject.com/weblog/2023/nov/01/security-releases

Affected versions of Django are vulnerable to Denial-of-Service via django.utils.text.Truncator. The django.utils.text.Truncator chars() and words() methods (when used with html=True) are subject to a potential DoS (denial of service) attack via certain inputs with very long, potentially malformed HTML text. The chars() and words() methods are used to implement the truncatechars_html and truncatewords_html template filters, which are thus also vulnerable. NOTE: this issue exists because of an incomplete fix for CVE-2019-14232.

Affected versions of Django are affected by a username enumeration vulnerability caused by timing differences in the django.contrib.auth.backends.ModelBackend.authenticate() method. This method allowed remote attackers to enumerate users through a timing attack involving login requests for users with unusable passwords. The timing difference in the authentication process exposed whether a username was valid or not, potentially aiding attackers in gaining unauthorized access.

Django 2.2.28, 3.2.13 and 4.0.4 include a fix for CVE-2022-28347: A SQL injection issue was discovered in QuerySet.explain() in Django 2.2 before 2.2.28, 3.2 before 3.2.13, and 4.0 before 4.0.4. This occurs by passing a crafted dictionary (with dictionary expansion) as the **options argument, and placing the injection payload in an option name.
https://www.djangoproject.com/weblog/2022/apr/11/security-releases

Django 2.2.16, 3.0.10 and 3.1.1 include a fix for CVE-2020-24583: An issue was discovered in Django 2.2 before 2.2.16, 3.0 before 3.0.10, and 3.1 before 3.1.1 (when Python 3.7+ is used). FILE_UPLOAD_DIRECTORY_PERMISSIONS mode was not applied to intermediate-level directories created in the process of uploading files. It was also not applied to intermediate-level collected static directories when using the collectstatic management command.
#NOTE: This vulnerability affects only users of Python versions above 3.7.
https://www.djangoproject.com/weblog/2020/sep/01/security-releases

Django 3.2.17, 4.0.9 and 4.1.6 includes a fix for CVE-2023-23969: In Django 3.2 before 3.2.17, 4.0 before 4.0.9, and 4.1 before 4.1.6, the parsed values of Accept-Language headers are cached in order to avoid repetitive parsing. This leads to a potential denial-of-service vector via excessive memory usage if the raw value of Accept-Language headers is very large.
https://www.djangoproject.com/weblog/2023/feb/01/security-releases

Affected versions of the `django` package are vulnerable to Download of Code Without Integrity Check due to improper handling of user-supplied input in the HTTP FileResponse class. The vulnerability arises because the Content-Disposition header of a FileResponse can be set using a filename derived from user input without sufficient validation. An attacker can exploit this by crafting a request that causes a file with malicious content to be downloaded, potentially executing arbitrary code on the client system when the file is opened.

CVE-2025-64459: Affected versions of the Django package are vulnerable to SQL Injection due to improper input validation, allowing the internal _connector keyword argument to be accepted from untrusted dictionaries via expansion. The .filter(), .exclude(), and .get() methods on QuerySet, as well as the Q class, resolve **kwargs and will treat a supplied _connector value as the logical connector without constraining it to the expected set (AND/OR), permitting attacker-controlled tokens to influence SQL predicate construction.

Affected versions of the Django package are vulnerable to SQL Injection due to insufficient input sanitization in FilteredRelation column aliases. The FilteredRelation class fails to properly validate or escape column alias names when they are provided through dictionary expansion as keyword arguments to QuerySet.annotate() or QuerySet.alias() methods, allowing malicious SQL code to be injected directly into the generated database queries.

Django fixes potential SQL injection in ``FilteredRelation`` column aliases on PostgreSQL.

Affected versions of the sqlparse package are vulnerable to Denial of Service (DoS) due to missing hard limits on token grouping recursion depth and token processing when formatting very large SQL tuple lists. During sqlparse.format() processing, the sqlparse.engine.grouping._group_matching() and sqlparse.engine.grouping._group() functions can recurse and iterate over excessively large tlist.tokens without enforcing MAX_GROUPING_DEPTH or MAX_GROUPING_TOKENS, allowing grouping work to grow until it effectively hangs.

Affected versions of this package are vulnerable to Denial of Service (DoS) attacks due to Algorithmic Complexity. The SQL parser fails to enforce limits when processing deeply nested tuples and large token sequences, leading to excessive resource consumption through crafted SQL statements with extreme nesting depth or token counts.

**Note:** This issue is due to an incomplete fix for CVE-2024-4340.

Sqlparse 0.5.0 addresses a potential denial of service (DoS) vulnerability related to recursion errors in deeply nested SQL statements. To mitigate this issue, the update replaces recursion errors with a general SQLParseError, improving the resilience and stability of the parsing process.

Sqlparse 0.4.4 includes a fix for CVE-2023-30608: Parser contains a regular expression that is vulnerable to ReDOS (Regular Expression Denial of Service).
https://github.com/andialbrecht/sqlparse/security/advisories/GHSA-rrm6-wvj7-cwh2

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to redirect handling that drains connections by decompressing redirect response bodies without enforcing streaming read limits. The issue occurs when using urllib3’s streaming mode (for example, preload_content=False) while allowing redirects, because urllib3.response.HTTPResponse.drain_conn() would call HTTPResponse.read() in a way that decoded/decompressed the entire redirect response body even before any streaming reads were performed, effectively bypassing decompression-bomb safeguards.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to improper handling of highly compressed HTTP response bodies during streaming decompression. The urllib3.HTTPResponse methods stream(), read(), read1(), read_chunked(), and readinto() may fully decompress a minimal but highly compressed payload based on the Content-Encoding header into an internal buffer instead of limiting the decompressed output to the requested chunk size, causing excessive CPU usage and massive memory allocation on the client side.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to allowing an unbounded number of content-encoding decompression steps for HTTP responses. The HTTPResponse content decoding pipeline in urllib3 follows the Content-Encoding header and applies each advertised compression algorithm in sequence without enforcing a maximum chain length or effective output size, so a malicious peer can send a response with a very long encoding chain that triggers excessive CPU use and massive memory allocation during decompression.

Urllib3's ProxyManager ensures that the Proxy-Authorization header is correctly directed only to configured proxies. However, when HTTP requests bypass urllib3's proxy support, there's a risk of inadvertently setting the Proxy-Authorization header, which remains ineffective without a forwarding or tunneling proxy. Urllib3 does not recognize this header as carrying authentication data, failing to remove it during cross-origin redirects. While this scenario is uncommon and poses low risk to most users, urllib3 now proactively removes the Proxy-Authorization header during cross-origin redirects as a precautionary measure. Users are advised to utilize urllib3's proxy support or disable automatic redirects to handle the Proxy-Authorization header securely. Despite these precautions, urllib3 defaults to stripping the header to safeguard users who may inadvertently misconfigure requests.

Urllib3 1.26.17 and 2.0.5 include a fix for CVE-2023-43804: Urllib3 doesn't treat the 'Cookie' HTTP header special or provide any helpers for managing cookies over HTTP, that is the responsibility of the user. However, it is possible for a user to specify a 'Cookie' header and unknowingly leak information via HTTP redirects to a different origin if that user doesn't disable redirects explicitly.
https://github.com/urllib3/urllib3/security/advisories/GHSA-v845-jxx5-vc9f

Urllib3 1.26.5 includes a fix for CVE-2021-33503: When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking, causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redirect.
https://github.com/advisories/GHSA-q2q7-5pp4-w6pg

The _encode_invalid_chars function in util/url.py in the urllib3 library 1.25.2 through 1.25.7 for Python allows a denial of service (CPU consumption) because of an inefficient algorithm. The percent_encodings array contains all matches of percent encodings. It is not deduplicated. For a URL of length N, the size of percent_encodings may be up to O(N). The next step (normalize existing percent-encoded bytes) also takes up to O(N) for each step, so the total time is O(N^2). If percent_encodings were deduplicated, the time to compute _encode_invalid_chars would be O(kN), where k is at most 484 ((10+6*2)^2). See: CVE-2020-7212.

Affected versions of urllib3 are vulnerable to an HTTP redirect handling vulnerability that fails to remove the HTTP request body when a POST changes to a GET via 301, 302, or 303 responses. This flaw can expose sensitive request data if the origin service is compromised and redirects to a malicious endpoint, though exploitability is low when no sensitive data is used. The vulnerability affects automatic redirect behavior. It is fixed in versions 1.26.18 and 2.0.7; update or disable redirects using redirects=False.
This vulnerability is specific to Python's urllib3 library.

urllib3 is a user-friendly HTTP client library for Python. Prior to 2.5.0, it is possible to disable redirects for all requests by instantiating a PoolManager and specifying retries in a way that disable redirects. By default, requests and botocore users are not affected. An application attempting to mitigate SSRF or open redirect vulnerabilities by disabling redirects at the PoolManager level will remain vulnerable. This issue has been patched in version 2.5.0.

Urllib3 1.25.9 includes a fix for CVE-2020-26137: Urllib3 before 1.25.9 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserting CR and LF control characters in the first argument of putrequest(). NOTE: this is similar to CVE-2020-26116.
https://github.com/python/cpython/issues/83784
https://github.com/urllib3/urllib3/pull/1800

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to redirect handling that drains connections by decompressing redirect response bodies without enforcing streaming read limits. The issue occurs when using urllib3’s streaming mode (for example, preload_content=False) while allowing redirects, because urllib3.response.HTTPResponse.drain_conn() would call HTTPResponse.read() in a way that decoded/decompressed the entire redirect response body even before any streaming reads were performed, effectively bypassing decompression-bomb safeguards.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to improper handling of highly compressed HTTP response bodies during streaming decompression. The urllib3.HTTPResponse methods stream(), read(), read1(), read_chunked(), and readinto() may fully decompress a minimal but highly compressed payload based on the Content-Encoding header into an internal buffer instead of limiting the decompressed output to the requested chunk size, causing excessive CPU usage and massive memory allocation on the client side.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to allowing an unbounded number of content-encoding decompression steps for HTTP responses. The HTTPResponse content decoding pipeline in urllib3 follows the Content-Encoding header and applies each advertised compression algorithm in sequence without enforcing a maximum chain length or effective output size, so a malicious peer can send a response with a very long encoding chain that triggers excessive CPU use and massive memory allocation during decompression.

Urllib3's ProxyManager ensures that the Proxy-Authorization header is correctly directed only to configured proxies. However, when HTTP requests bypass urllib3's proxy support, there's a risk of inadvertently setting the Proxy-Authorization header, which remains ineffective without a forwarding or tunneling proxy. Urllib3 does not recognize this header as carrying authentication data, failing to remove it during cross-origin redirects. While this scenario is uncommon and poses low risk to most users, urllib3 now proactively removes the Proxy-Authorization header during cross-origin redirects as a precautionary measure. Users are advised to utilize urllib3's proxy support or disable automatic redirects to handle the Proxy-Authorization header securely. Despite these precautions, urllib3 defaults to stripping the header to safeguard users who may inadvertently misconfigure requests.

Urllib3 1.26.17 and 2.0.5 include a fix for CVE-2023-43804: Urllib3 doesn't treat the 'Cookie' HTTP header special or provide any helpers for managing cookies over HTTP, that is the responsibility of the user. However, it is possible for a user to specify a 'Cookie' header and unknowingly leak information via HTTP redirects to a different origin if that user doesn't disable redirects explicitly.
https://github.com/urllib3/urllib3/security/advisories/GHSA-v845-jxx5-vc9f

Urllib3 1.26.5 includes a fix for CVE-2021-33503: When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking, causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redirect.
https://github.com/advisories/GHSA-q2q7-5pp4-w6pg

The _encode_invalid_chars function in util/url.py in the urllib3 library 1.25.2 through 1.25.7 for Python allows a denial of service (CPU consumption) because of an inefficient algorithm. The percent_encodings array contains all matches of percent encodings. It is not deduplicated. For a URL of length N, the size of percent_encodings may be up to O(N). The next step (normalize existing percent-encoded bytes) also takes up to O(N) for each step, so the total time is O(N^2). If percent_encodings were deduplicated, the time to compute _encode_invalid_chars would be O(kN), where k is at most 484 ((10+6*2)^2). See: CVE-2020-7212.

Affected versions of urllib3 are vulnerable to an HTTP redirect handling vulnerability that fails to remove the HTTP request body when a POST changes to a GET via 301, 302, or 303 responses. This flaw can expose sensitive request data if the origin service is compromised and redirects to a malicious endpoint, though exploitability is low when no sensitive data is used. The vulnerability affects automatic redirect behavior. It is fixed in versions 1.26.18 and 2.0.7; update or disable redirects using redirects=False.
This vulnerability is specific to Python's urllib3 library.

urllib3 is a user-friendly HTTP client library for Python. Prior to 2.5.0, it is possible to disable redirects for all requests by instantiating a PoolManager and specifying retries in a way that disable redirects. By default, requests and botocore users are not affected. An application attempting to mitigate SSRF or open redirect vulnerabilities by disabling redirects at the PoolManager level will remain vulnerable. This issue has been patched in version 2.5.0.

Urllib3 1.25.9 includes a fix for CVE-2020-26137: Urllib3 before 1.25.9 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserting CR and LF control characters in the first argument of putrequest(). NOTE: this is similar to CVE-2020-26116.
https://github.com/python/cpython/issues/83784
https://github.com/urllib3/urllib3/pull/1800

Affected versions of the gunicorn package are vulnerable to HTTP Request/Response Smuggling due to improper validation of the Transfer-Encoding header that enables a TE.CL desynchronisation condition. Gunicorn’s HTTP parser does not consistently enforce RFC semantics when parsing conflicting or unsupported request framing—such as messages containing both Transfer-Encoding and Content-Length—so the backend may fall back to Content-Length while an intermediary treats the message as chunked.

Gunicorn 20.0.1 fixes chunked encoding support to prevent http request smuggling attacks.
https://github.com/benoitc/gunicorn/issues/2176
https://github.com/p4k03n4t0r/http-request-smuggling#request-smuggling-using-mitmproxy-and-gunicorn

Gunicorn fails to properly validate Transfer-Encoding headers, leading to HTTP Request Smuggling (HRS) vulnerabilities. By crafting requests with conflicting Transfer-Encoding headers, attackers can bypass security restrictions and access restricted endpoints. This issue is due to Gunicorn's handling of Transfer-Encoding headers, where it incorrectly processes requests with multiple, conflicting Transfer-Encoding headers, treating them as chunked regardless of the final encoding specified. This vulnerability allows for a range of attacks including cache poisoning, session manipulation, and data exposure.

Requests is an HTTP library. Due to a URL parsing issue, Requests releases prior to 2.32.4 may leak .netrc credentials to third parties for specific maliciously-crafted URLs. Users should upgrade to version 2.32.4 to receive a fix. For older versions of Requests, use of the .netrc file can be disabled with `trust_env=False` on one's Requests Session.

Affected versions of Requests are vulnerable to proxy credential leakage. When redirected to an HTTPS endpoint, the Proxy-Authorization header is forwarded to the destination server due to the use of rebuild_proxies to reattach the header. This may allow a malicious actor to exfiltrate sensitive information.

Affected versions of the requests package are vulnerable to Insecure Temporary File reuse due to predictable temporary filename generation in extract_zipped_paths(). The requests.utils.extract_zipped_paths() utility extracts files from zip archives into the system temporary directory using a deterministic path, and if that file already exists, the function reuses it without validating that it is the expected extracted content.

Affected versions of Requests, when making requests through a Requests `Session`, if the first request is made with `verify=False` to disable cert verification, all subsequent requests to the same host will continue to ignore cert verification regardless of changes to the value of `verify`. This behavior will continue for the lifecycle of the connection in the connection pool. Requests 2.32.0 fixes the issue, but versions 2.32.0 and 2.32.1 were yanked due to conflicts with CVE-2024-35195 mitigation.

Certifi 2022.12.07 includes a fix for CVE-2022-23491: Certifi 2022.12.07 removes root certificates from "TrustCor" from the root store. These are in the process of being removed from Mozilla's trust store. TrustCor's root certificates are being removed pursuant to an investigation prompted by media reporting that TrustCor's ownership also operated a business that produced spyware. Conclusions of Mozilla's investigation can be found in the linked google group discussion.

Certifi 2023.07.22 includes a fix for CVE-2023-37920: Certifi prior to version 2023.07.22 recognizes "e-Tugra" root certificates. e-Tugra's root certificates were subject to an investigation prompted by reporting of security issues in their systems. Certifi 2023.07.22 removes root certificates from "e-Tugra" from the root store.
https://github.com/certifi/python-certifi/security/advisories/GHSA-xqr8-7jwr-rhp7

Certifi 2022.12.07 includes a fix for CVE-2022-23491: Certifi 2022.12.07 removes root certificates from "TrustCor" from the root store. These are in the process of being removed from Mozilla's trust store. TrustCor's root certificates are being removed pursuant to an investigation prompted by media reporting that TrustCor's ownership also operated a business that produced spyware. Conclusions of Mozilla's investigation can be found in the linked google group discussion.

Certifi 2023.07.22 includes a fix for CVE-2023-37920: Certifi prior to version 2023.07.22 recognizes "e-Tugra" root certificates. e-Tugra's root certificates were subject to an investigation prompted by reporting of security issues in their systems. Certifi 2023.07.22 removes root certificates from "e-Tugra" from the root store.
https://github.com/certifi/python-certifi/security/advisories/GHSA-xqr8-7jwr-rhp7

Affected versions of Sentry's Python SDK are vulnerable to unintentional exposure of environment variables to subprocesses despite the env={} setting. In Python's 'subprocess' calls, all environment variables are passed to subprocesses by default. However, if you specifically do not want them to be passed to subprocesses, you may use 'env' argument in 'subprocess' calls. Due to the bug in Sentry SDK, with the Stdlib integration enabled (which is enabled by default), this expectation is not fulfilled, and all environment variables are being passed to subprocesses instead. 
As a workaround, and if passing environment variables to child processes poses a security risk for you, you can disable all default integrations.

Sentry-sdk 1.14.0 includes a fix for CVE-2023-28117: When using the Django integration of versions prior to 1.14.0 of the Sentry SDK in a specific configuration it is possible to leak sensitive cookies values, including the session cookie to Sentry. These sensitive cookies could then be used by someone with access to your Sentry issues to impersonate or escalate their privileges within your application. In order for these sensitive values to be leaked, the Sentry SDK configuration must have 'sendDefaultPII' set to 'True'; one must use a custom name for either 'SESSION_COOKIE_NAME' or 'CSRF_COOKIE_NAME' in one's Django settings; and one must not be configured in one's organization or project settings to use Sentry's data scrubbing features to account for the custom cookie names. As of version 1.14.0, the Django integration of the 'sentry-sdk' will detect the custom cookie names based on one's Django settings and will remove the values from the payload before sending the data to Sentry. As a workaround, use the SDK's filtering mechanism to remove the cookies from the payload that is sent to Sentry. For error events, this can be done with the 'before_send' callback method and for performance related events (transactions) one can use the 'before_send_transaction' callback method. Those who want to handle filtering of these values on the server-side can also use Sentry's advanced data scrubbing feature to account for the custom cookie names. Look for the '$http.cookies', '$http.headers', '$request.cookies', or '$request.headers' fields to target with a scrubbing rule.
https://github.com/getsentry/sentry-python/security/advisories/GHSA-29pr-6jr8-q5jm

Sentry-sdk 1.4.1 includes a fix for a Race Condition vulnerability.
https://github.com/getsentry/sentry-python/pull/1203

A SQL Injection issue in the SQL Panel in Jazzband Django Debug Toolbar before 1.11.1, 2.x before 2.2.1, and 3.x before 3.2.1 allows attackers to execute SQL statements by changing the raw_sql input field of the SQL explain, analyze, or select form. See CVE-2021-30459.

** DISPUTED ** Py throughout 1.11.0 allows remote attackers to conduct a ReDoS (Regular expression Denial of Service) attack via a Subversion repository with crafted info data because the InfoSvnCommand argument is mishandled.
https://github.com/pytest-dev/py/issues/287

Py 1.10.0 includes a fix for CVE-2020-29651: A denial of service via regular expression in the py.path.svnwc component of py (aka python-py) through 1.9.0 could be used by attackers to cause a compute-time denial of service attack by supplying malicious input to the blame functionality.

Affected versions of Idna are vulnerable to Denial Of Service via the idna.encode(), where a specially crafted argument could lead to significant resource consumption. In version 3.7, this function has been updated to reject such inputs efficiently, minimizing resource use. A practical workaround involves enforcing a maximum domain name length of 253 characters before encoding, as the vulnerability is triggered by unusually large inputs that normal operations wouldn't encounter.

** DISPUTED ** Py throughout 1.11.0 allows remote attackers to conduct a ReDoS (Regular expression Denial of Service) attack via a Subversion repository with crafted info data because the InfoSvnCommand argument is mishandled.
https://github.com/pytest-dev/py/issues/287

Py 1.10.0 includes a fix for CVE-2020-29651: A denial of service via regular expression in the py.path.svnwc component of py (aka python-py) through 1.9.0 could be used by attackers to cause a compute-time denial of service attack by supplying malicious input to the blame functionality.

An issue was discovered in Django 2.2 before 2.2.13 and 3.0 before 3.0.7. Query parameters generated by the Django admin ForeignKeyRawIdWidget were not properly URL encoded, leading to a possibility of an XSS attack.

Affected versions of the Django package are vulnerable to SQL Injection due to improper handling of control characters in column aliases within FilteredRelation. The FilteredRelation class fails to properly sanitize column aliases containing control characters when used with QuerySet methods annotate(), aggregate(), extra(), values(), values_list(), and alias() via dictionary expansion (**kwargs).

Affected versions of the Django package are vulnerable to SQL Injection due to improper sanitization of band index parameters in PostGIS raster lookups. The raster lookup functionality in Django's GIS module fails to properly validate or escape untrusted data used as a band index when performing spatial queries against PostGIS databases.

Affected versions of Django are vulnerable to potential denial-of-service in intcomma template filter when used with very long strings.

A potential denial-of-service vulnerability has been identified in Django's urlize() and urlizetrunc() functions in django.utils.html. This vulnerability can be triggered by inputting huge strings containing a specific sequence of characters.

Django 3.2.14 and 4.0.6 include a fix for CVE-2022-34265: Potential SQL injection via Trunc(kind) and Extract(lookup_name) arguments.
https://www.djangoproject.com/weblog/2022/jul/04/security-releases

An issue was discovered in Django 2.2 before 2.2.13 and 3.0 before 3.0.7. In cases where a memcached backend does not perform key validation, passing malformed cache keys could result in a key collision, and potential data leakage.

Django 4.1.7, 4.0.10 and 3.2.18 include a fix for CVE-2023-24580: Potential denial-of-service vulnerability in file uploads.
https://www.djangoproject.com/weblog/2023/feb/14/security-releases

An issue was discovered in Django 2.2 before 2.2.16, 3.0 before 3.0.10, and 3.1 before 3.1.1 (when Python 3.7+ is used). The intermediate-level directories of the filesystem cache had the system's standard umask rather than 0o077.

Django versions 3.2.2, 3.1.10 and 2.2.22 include a fix for CVE-2021-32052: In Django 2.2 before 2.2.22, 3.1 before 3.1.10, and 3.2 before 3.2.2 (with Python 3.9.5+), URLValidator does not prohibit newlines and tabs (unless the URLField form field is used). If an application uses values with newlines in an HTTP response, header injection can occur. Django itself is unaffected because HttpResponse prohibits newlines in HTTP headers.
https://www.djangoproject.com/weblog/2021/may/06/security-releases

Affected versions of the Django package are vulnerable to Path Traversal due to improper validation of file paths in the django.contrib.admindocs module. The `TemplateDetailView` view allows staff members to verify the existence of arbitrary files by manipulating the file path. An attacker with staff privileges can exploit this vulnerability to check for the presence of files outside the template root directories, and if the `admindocs` templates are customized to display file contents, they can also access the contents of these files.

Django addresses a memory exhaustion issue in django.utils.numberformat.floatformat(). When floatformat receives a string representation of a number in scientific notation with a large exponent, it could lead to excessive memory consumption. To prevent this, decimals with more than 200 digits are now returned as-is.

Django 2.2.24, 3.1.12, and 3.2.4 include a fix for CVE-2021-33571: In Django 2.2 before 2.2.24, 3.x before 3.1.12, and 3.2 before 3.2.4, URLValidator, validate_ipv4_address, and validate_ipv46_address do not prohibit leading zero characters in octal literals. This may allow a bypass of access control that is based on IP addresses. (validate_ipv4_address and validate_ipv46_address are unaffected with Python 3.9.5+).
https://www.djangoproject.com/weblog/2021/jun/02/security-releases

Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to inefficient string concatenation when processing duplicate HTTP headers in ASGI mode. The ASGIRequest class combines repeated headers using repeated string concatenation, resulting in super-linear (quadratic) time complexity when processing requests with many duplicate headers.

Affected versions of the Django package are vulnerable to SQL Injection due to improper handling of column aliases containing periods in QuerySet.order_by() when combined with FilteredRelation. The QuerySet.order_by() method fails to properly sanitize column aliases that contain periods when the same alias is used in FilteredRelation via dictionary expansion. 
https://github.com/django/django/commit/90f5b10784ba5bf369caed87640e2b4394ea3314

Django 2.2.21, 3.1.9 and 3.2.1 include a fix for CVE-2021-31542: MultiPartParser, UploadedFile, and FieldFile allowed directory traversal via uploaded files with suitably crafted file names.
https://www.djangoproject.com/weblog/2021/may/04/security-releases

An issue was discovered in Django 4.2 before 4.2.21, 5.1 before 5.1.9, and 5.2 before 5.2.1. The django.utils.html.strip_tags() function is vulnerable to a potential denial-of-service (slow performance) when processing inputs containing large sequences of incomplete HTML tags. The template filter striptags is also vulnerable, because it is built on top of strip_tags().

In Django 3.2 before 3.2.16, 4.0 before 4.0.8, and 4.1 before 4.1.2, internationalized URLs were subject to a potential denial of service attack via the locale parameter, which is treated as a regular expression.

Affected versions of Django are vulnerable to potential Denial of Service via certain inputs with a very large number of Unicode characters in django.utils.encoding.uri_to_iri().

Django 1.11.29, 2.2.11 and 3.0.4 includes a fix for CVE-2020-9402: Django 1.11 before 1.11.29, 2.2 before 2.2.11, and 3.0 before 3.0.4 allows SQL Injection if untrusted data is used as a tolerance parameter in GIS functions and aggregates on Oracle. By passing a suitably crafted tolerance to GIS functions and aggregates on Oracle, it was possible to break escaping and inject malicious SQL.
https://www.djangoproject.com/weblog/2020/mar/04/security-releases

Django affected versions are vulnerable to a potential SQL injection in the HasKey(lhs, rhs) lookup on Oracle databases. The vulnerability arises when untrusted data is directly used as the lhs value in the django.db.models.fields.json.HasKey lookup. However, applications using the jsonfield.has_key lookup with the __ syntax remain unaffected by this issue.

Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to quadratic time complexity during HTML parsing in text truncation methods. The django.utils.text.Truncator.chars() and Truncator.words() methods (with html=True), as well as the truncatechars_html and truncatewords_html template filters, exhibit quadratic time complexity when processing inputs containing a large number of unmatched HTML end tags.

Django versions 2.2.25, 3.1.14 and 3.2.10 include a fix for CVE-2021-44420: In Django 2.2 before 2.2.25, 3.1 before 3.1.14, and 3.2 before 3.2.10, HTTP requests for URLs with trailing newlines could bypass upstream access control based on URL paths.
https://www.djangoproject.com/weblog/2021/dec/07/security-releases/

Django 2.1.15 and 2.2.8 includes a fix for CVE-2019-19118: A Django model admin displaying inline related models, where the user has view-only permissions to a parent model but edit permissions to the inline model, would be presented with an editing UI, allowing POST requests, for updating the inline model. Directly editing the view-only parent model was not possible, but the parent model's save() method was called, triggering potential side effects, and causing pre and post-save signal handlers to be invoked. To resolve this, the Django admin is adjusted to require edit permissions on the parent model in order for inline models to be editable.

Django 1.11.27, 2.2.9 and 3.0.1 include a fix for CVE-2019-19844: Account takeover. A suitably crafted email address (that is equal to an existing user's email address after case transformation of Unicode characters) would allow an attacker to be sent a password reset token for the matched user account. One mitigation in the new releases is to send password reset tokens only to the registered user email address.

Django has a potential denial-of-service vulnerability in django.utils.html.urlize() and AdminURLFieldWidget. The urlize and urlizetrunc functions, along with AdminURLFieldWidget, are vulnerable to denial-of-service attacks when handling inputs with a very large number of Unicode characters.

Affected versions of Django are potentially vulnerable to denial-of-service via the get_supported_language_variant() method. This method was susceptible to a denial-of-service attack when used with very long strings containing specific characters. Exploiting this vulnerability could cause significant delays or crashes in the affected application, potentially leading to service disruption.

Django versions 2.2.19, 3.0.13 and 3.1.7 include a fix for CVE-2021-23336: Web cache poisoning via 'django.utils.http.limited_parse_qsl()'. Django contains a copy of 'urllib.parse.parse_qsl' which was added to backport some security fixes. A further security fix has been issued recently such that 'parse_qsl(' no longer allows using ';' as a query parameter separator by default.

Django 4.2.1, 4.1.9 and 3.2.19 include a fix for CVE-2023-31047: In Django 3.2 before 3.2.19, 4.x before 4.1.9, and 4.2 before 4.2.1, it was possible to bypass validation when using one form field to upload multiple files. This multiple upload has never been supported by forms.FileField or forms.ImageField (only the last uploaded file was validated). However, Django's "Uploading multiple files" documentation suggested otherwise.
https://www.djangoproject.com/weblog/2023/may/03/security-releases

Affected versions of Django are vulnerable to potential regular expression denial-of-service (REDoS). django.utils.text.Truncator.words() method (with html=True) and truncatewords_html template filter were subject to a potential regular expression denial-of-service attack using a suitably crafted string (follow up to CVE-2019-14232 and CVE-2023-43665).

Affected versions of Django are vulnerable to a potential ReDoS (regular expression denial of service) in EmailValidator and URLValidator via a very large number of domain name labels of emails and URLs.

Django 2.2.27, 3.2.12 and 4.0.2 include a fix for CVE-2022-23833: Denial-of-service possibility in file uploads.
https://www.djangoproject.com/weblog/2022/feb/01/security-releases

Django 2.2.28, 3.2.13 and 4.0.4 include a fix for CVE-2022-28346: An issue was discovered in Django 2.2 before 2.2.28, 3.2 before 3.2.13, and 4.0 before 4.0.4. QuerySet.annotate(), aggregate(), and extra() methods are subject to SQL injection in column aliases via a crafted dictionary (with dictionary expansion) as the passed **kwargs.
https://www.djangoproject.com/weblog/2022/apr/11/security-releases

In Django 2.2 before 2.2.20, 3.0 before 3.0.14, and 3.1 before 3.1.8, MultiPartParser allowed directory traversal via uploaded files with suitably crafted file names. Built-in upload handlers were not affected by this vulnerability.

CVE-2025-64458: Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to slow Unicode NFKC normalization on Windows being applied to untrusted inputs. The django.contrib.auth.views.LoginView and django.contrib.auth.views.LogoutView, and django.views.i18n.set_language normalize user-controlled strings using Python’s NFKC algorithm, which is unusually slow on Windows for huge Unicode sequences and can be triggered to consume excessive CPU.

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45452: Storage.save in Django 2.2 before 2.2.26, 3.2 before 3.2.11, and 4.0 before 4.0.1 allows directory traversal if crafted filenames are directly passed to it.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases/

Affected versions of Django are vulnerable to a potential denial-of-service (DoS) attack in the `django.utils.html.strip_tags()` method. The vulnerability occurs when the `strip_tags()` method or the `striptags` template filter processes inputs containing large sequences of nested, incomplete HTML entities.

Affected versions of the Django package are vulnerable to Information Disclosure (Timing Attack) due to non-constant-time comparison in the mod_wsgi authentication handler. The django.contrib.auth.handlers.modwsgi.check_password() function does not perform user existence checks in constant time, allowing response timing differences to reveal whether usernames exist.

The {% debug %} template tag in Django 2.2 before 2.2.27, 3.2 before 3.2.12, and 4.0 before 4.0.2 does not properly encode the current context. This may lead to XSS.

Django fixes a potential denial-of-service vulnerability in XML ``Deserializer``.

An issue was discovered in Django 5.2 before 5.2.3, 5.1 before 5.1.11, and 4.2 before 4.2.23. Internal HTTP response logging does not escape request.path, which allows remote attackers to potentially manipulate log output via crafted URLs. This may lead to log injection or forgery when logs are viewed in terminals or processed by external systems.

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45116: An issue was discovered in Django 2.2 before 2.2.26, 3.2 before 3.2.11, and 4.0 before 4.0.1. Due to leveraging the Django Template Language's variable resolution logic, the dictsort template filter was potentially vulnerable to information disclosure, or an unintended method call, if passed a suitably crafted key.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45115: UserAttributeSimilarityValidator incurred significant overhead in evaluating a submitted password that was artificially large in relation to the comparison values. In a situation where access to user registration was unrestricted, this provided a potential vector for a denial-of-service attack.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases/

Affected versions of Django are affected by a potential denial-of-service vulnerability in the django.utils.html.urlize() function. The urlize and urlizetrunc template filters were susceptible to a denial-of-service attack via certain inputs containing many brackets. An attacker could exploit this vulnerability to cause significant delays or crashes in the affected application.

Affected versions of Django are affected by a directory-traversal vulnerability in the Storage.save() method. Derived classes of the django.core.files.storage.Storage base class that overrides the generate_filename() method without replicating the file path validations existing in the parent class could allow for directory traversal via certain inputs when calling save(). This could enable an attacker to manipulate file paths and access unintended directories.

Django 1.11.28, 2.2.10 and 3.0.3 include a fix for CVE-2020-7471: SQL Injection if untrusted data is used as a StringAgg delimiter (e.g., in Django applications that offer downloads of data as a series of rows with a user-specified column delimiter). By passing a suitably crafted delimiter to a contrib.postgres.aggregates.StringAgg instance, it was possible to break escaping and inject malicious SQL.

Affected versions of Django has a potential SQL injection vulnerability in the QuerySet.values() and QuerySet.values_list() methods. When used on models with a JSONField, these methods are susceptible to SQL injection through column aliases if a crafted JSON object key is passed as an argument.

A security vulnerability has been discovered in certain versions of Django, affecting the password reset functionality. The PasswordResetForm class in django.contrib.auth.forms inadvertently allowed attackers to enumerate user email addresses by exploiting unhandled exceptions during the email sending process. This could be done by issuing password reset requests and observing the responses. Django has implemented a fix where these exceptions are now caught and logged using the django.contrib.auth logger, preventing potential information leakage through error responses.

Django 2.2.18, 3.0.12 and 3.1.6 include a fix for CVE-2021-3281: The django.utils.archive.extract method (used by "startapp --template" and "startproject --template") allows directory traversal via an archive with absolute paths or relative paths with dot segments.

Django 4.2.7, 4.1.13 and 3.2.23 include a fix for CVE-2023-46695: Potential denial of service vulnerability in UsernameField on Windows.
https://www.djangoproject.com/weblog/2023/nov/01/security-releases

Affected versions of Django are vulnerable to Denial-of-Service via django.utils.text.Truncator. The django.utils.text.Truncator chars() and words() methods (when used with html=True) are subject to a potential DoS (denial of service) attack via certain inputs with very long, potentially malformed HTML text. The chars() and words() methods are used to implement the truncatechars_html and truncatewords_html template filters, which are thus also vulnerable. NOTE: this issue exists because of an incomplete fix for CVE-2019-14232.

Affected versions of Django are affected by a username enumeration vulnerability caused by timing differences in the django.contrib.auth.backends.ModelBackend.authenticate() method. This method allowed remote attackers to enumerate users through a timing attack involving login requests for users with unusable passwords. The timing difference in the authentication process exposed whether a username was valid or not, potentially aiding attackers in gaining unauthorized access.

Django 2.2.28, 3.2.13 and 4.0.4 include a fix for CVE-2022-28347: A SQL injection issue was discovered in QuerySet.explain() in Django 2.2 before 2.2.28, 3.2 before 3.2.13, and 4.0 before 4.0.4. This occurs by passing a crafted dictionary (with dictionary expansion) as the **options argument, and placing the injection payload in an option name.
https://www.djangoproject.com/weblog/2022/apr/11/security-releases

Django 2.2.16, 3.0.10 and 3.1.1 include a fix for CVE-2020-24583: An issue was discovered in Django 2.2 before 2.2.16, 3.0 before 3.0.10, and 3.1 before 3.1.1 (when Python 3.7+ is used). FILE_UPLOAD_DIRECTORY_PERMISSIONS mode was not applied to intermediate-level directories created in the process of uploading files. It was also not applied to intermediate-level collected static directories when using the collectstatic management command.
#NOTE: This vulnerability affects only users of Python versions above 3.7.
https://www.djangoproject.com/weblog/2020/sep/01/security-releases

Django 3.2.17, 4.0.9 and 4.1.6 includes a fix for CVE-2023-23969: In Django 3.2 before 3.2.17, 4.0 before 4.0.9, and 4.1 before 4.1.6, the parsed values of Accept-Language headers are cached in order to avoid repetitive parsing. This leads to a potential denial-of-service vector via excessive memory usage if the raw value of Accept-Language headers is very large.
https://www.djangoproject.com/weblog/2023/feb/01/security-releases

Affected versions of the `django` package are vulnerable to Download of Code Without Integrity Check due to improper handling of user-supplied input in the HTTP FileResponse class. The vulnerability arises because the Content-Disposition header of a FileResponse can be set using a filename derived from user input without sufficient validation. An attacker can exploit this by crafting a request that causes a file with malicious content to be downloaded, potentially executing arbitrary code on the client system when the file is opened.

CVE-2025-64459: Affected versions of the Django package are vulnerable to SQL Injection due to improper input validation, allowing the internal _connector keyword argument to be accepted from untrusted dictionaries via expansion. The .filter(), .exclude(), and .get() methods on QuerySet, as well as the Q class, resolve **kwargs and will treat a supplied _connector value as the logical connector without constraining it to the expected set (AND/OR), permitting attacker-controlled tokens to influence SQL predicate construction.

Affected versions of the Django package are vulnerable to SQL Injection due to insufficient input sanitization in FilteredRelation column aliases. The FilteredRelation class fails to properly validate or escape column alias names when they are provided through dictionary expansion as keyword arguments to QuerySet.annotate() or QuerySet.alias() methods, allowing malicious SQL code to be injected directly into the generated database queries.

Django fixes potential SQL injection in ``FilteredRelation`` column aliases on PostgreSQL.

Affected versions of the sqlparse package are vulnerable to Denial of Service (DoS) due to missing hard limits on token grouping recursion depth and token processing when formatting very large SQL tuple lists. During sqlparse.format() processing, the sqlparse.engine.grouping._group_matching() and sqlparse.engine.grouping._group() functions can recurse and iterate over excessively large tlist.tokens without enforcing MAX_GROUPING_DEPTH or MAX_GROUPING_TOKENS, allowing grouping work to grow until it effectively hangs.

Affected versions of this package are vulnerable to Denial of Service (DoS) attacks due to Algorithmic Complexity. The SQL parser fails to enforce limits when processing deeply nested tuples and large token sequences, leading to excessive resource consumption through crafted SQL statements with extreme nesting depth or token counts.

**Note:** This issue is due to an incomplete fix for CVE-2024-4340.

Sqlparse 0.5.0 addresses a potential denial of service (DoS) vulnerability related to recursion errors in deeply nested SQL statements. To mitigate this issue, the update replaces recursion errors with a general SQLParseError, improving the resilience and stability of the parsing process.

Sqlparse 0.4.4 includes a fix for CVE-2023-30608: Parser contains a regular expression that is vulnerable to ReDOS (Regular Expression Denial of Service).
https://github.com/andialbrecht/sqlparse/security/advisories/GHSA-rrm6-wvj7-cwh2

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to redirect handling that drains connections by decompressing redirect response bodies without enforcing streaming read limits. The issue occurs when using urllib3’s streaming mode (for example, preload_content=False) while allowing redirects, because urllib3.response.HTTPResponse.drain_conn() would call HTTPResponse.read() in a way that decoded/decompressed the entire redirect response body even before any streaming reads were performed, effectively bypassing decompression-bomb safeguards.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to improper handling of highly compressed HTTP response bodies during streaming decompression. The urllib3.HTTPResponse methods stream(), read(), read1(), read_chunked(), and readinto() may fully decompress a minimal but highly compressed payload based on the Content-Encoding header into an internal buffer instead of limiting the decompressed output to the requested chunk size, causing excessive CPU usage and massive memory allocation on the client side.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to allowing an unbounded number of content-encoding decompression steps for HTTP responses. The HTTPResponse content decoding pipeline in urllib3 follows the Content-Encoding header and applies each advertised compression algorithm in sequence without enforcing a maximum chain length or effective output size, so a malicious peer can send a response with a very long encoding chain that triggers excessive CPU use and massive memory allocation during decompression.

Urllib3's ProxyManager ensures that the Proxy-Authorization header is correctly directed only to configured proxies. However, when HTTP requests bypass urllib3's proxy support, there's a risk of inadvertently setting the Proxy-Authorization header, which remains ineffective without a forwarding or tunneling proxy. Urllib3 does not recognize this header as carrying authentication data, failing to remove it during cross-origin redirects. While this scenario is uncommon and poses low risk to most users, urllib3 now proactively removes the Proxy-Authorization header during cross-origin redirects as a precautionary measure. Users are advised to utilize urllib3's proxy support or disable automatic redirects to handle the Proxy-Authorization header securely. Despite these precautions, urllib3 defaults to stripping the header to safeguard users who may inadvertently misconfigure requests.

Urllib3 1.26.17 and 2.0.5 include a fix for CVE-2023-43804: Urllib3 doesn't treat the 'Cookie' HTTP header special or provide any helpers for managing cookies over HTTP, that is the responsibility of the user. However, it is possible for a user to specify a 'Cookie' header and unknowingly leak information via HTTP redirects to a different origin if that user doesn't disable redirects explicitly.
https://github.com/urllib3/urllib3/security/advisories/GHSA-v845-jxx5-vc9f

Urllib3 1.26.5 includes a fix for CVE-2021-33503: When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking, causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redirect.
https://github.com/advisories/GHSA-q2q7-5pp4-w6pg

The _encode_invalid_chars function in util/url.py in the urllib3 library 1.25.2 through 1.25.7 for Python allows a denial of service (CPU consumption) because of an inefficient algorithm. The percent_encodings array contains all matches of percent encodings. It is not deduplicated. For a URL of length N, the size of percent_encodings may be up to O(N). The next step (normalize existing percent-encoded bytes) also takes up to O(N) for each step, so the total time is O(N^2). If percent_encodings were deduplicated, the time to compute _encode_invalid_chars would be O(kN), where k is at most 484 ((10+6*2)^2). See: CVE-2020-7212.

Affected versions of urllib3 are vulnerable to an HTTP redirect handling vulnerability that fails to remove the HTTP request body when a POST changes to a GET via 301, 302, or 303 responses. This flaw can expose sensitive request data if the origin service is compromised and redirects to a malicious endpoint, though exploitability is low when no sensitive data is used. The vulnerability affects automatic redirect behavior. It is fixed in versions 1.26.18 and 2.0.7; update or disable redirects using redirects=False.
This vulnerability is specific to Python's urllib3 library.

urllib3 is a user-friendly HTTP client library for Python. Prior to 2.5.0, it is possible to disable redirects for all requests by instantiating a PoolManager and specifying retries in a way that disable redirects. By default, requests and botocore users are not affected. An application attempting to mitigate SSRF or open redirect vulnerabilities by disabling redirects at the PoolManager level will remain vulnerable. This issue has been patched in version 2.5.0.

Urllib3 1.25.9 includes a fix for CVE-2020-26137: Urllib3 before 1.25.9 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserting CR and LF control characters in the first argument of putrequest(). NOTE: this is similar to CVE-2020-26116.
https://github.com/python/cpython/issues/83784
https://github.com/urllib3/urllib3/pull/1800

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to redirect handling that drains connections by decompressing redirect response bodies without enforcing streaming read limits. The issue occurs when using urllib3’s streaming mode (for example, preload_content=False) while allowing redirects, because urllib3.response.HTTPResponse.drain_conn() would call HTTPResponse.read() in a way that decoded/decompressed the entire redirect response body even before any streaming reads were performed, effectively bypassing decompression-bomb safeguards.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to improper handling of highly compressed HTTP response bodies during streaming decompression. The urllib3.HTTPResponse methods stream(), read(), read1(), read_chunked(), and readinto() may fully decompress a minimal but highly compressed payload based on the Content-Encoding header into an internal buffer instead of limiting the decompressed output to the requested chunk size, causing excessive CPU usage and massive memory allocation on the client side.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to allowing an unbounded number of content-encoding decompression steps for HTTP responses. The HTTPResponse content decoding pipeline in urllib3 follows the Content-Encoding header and applies each advertised compression algorithm in sequence without enforcing a maximum chain length or effective output size, so a malicious peer can send a response with a very long encoding chain that triggers excessive CPU use and massive memory allocation during decompression.

Urllib3's ProxyManager ensures that the Proxy-Authorization header is correctly directed only to configured proxies. However, when HTTP requests bypass urllib3's proxy support, there's a risk of inadvertently setting the Proxy-Authorization header, which remains ineffective without a forwarding or tunneling proxy. Urllib3 does not recognize this header as carrying authentication data, failing to remove it during cross-origin redirects. While this scenario is uncommon and poses low risk to most users, urllib3 now proactively removes the Proxy-Authorization header during cross-origin redirects as a precautionary measure. Users are advised to utilize urllib3's proxy support or disable automatic redirects to handle the Proxy-Authorization header securely. Despite these precautions, urllib3 defaults to stripping the header to safeguard users who may inadvertently misconfigure requests.

Urllib3 1.26.17 and 2.0.5 include a fix for CVE-2023-43804: Urllib3 doesn't treat the 'Cookie' HTTP header special or provide any helpers for managing cookies over HTTP, that is the responsibility of the user. However, it is possible for a user to specify a 'Cookie' header and unknowingly leak information via HTTP redirects to a different origin if that user doesn't disable redirects explicitly.
https://github.com/urllib3/urllib3/security/advisories/GHSA-v845-jxx5-vc9f

Urllib3 1.26.5 includes a fix for CVE-2021-33503: When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking, causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redirect.
https://github.com/advisories/GHSA-q2q7-5pp4-w6pg

The _encode_invalid_chars function in util/url.py in the urllib3 library 1.25.2 through 1.25.7 for Python allows a denial of service (CPU consumption) because of an inefficient algorithm. The percent_encodings array contains all matches of percent encodings. It is not deduplicated. For a URL of length N, the size of percent_encodings may be up to O(N). The next step (normalize existing percent-encoded bytes) also takes up to O(N) for each step, so the total time is O(N^2). If percent_encodings were deduplicated, the time to compute _encode_invalid_chars would be O(kN), where k is at most 484 ((10+6*2)^2). See: CVE-2020-7212.

Affected versions of urllib3 are vulnerable to an HTTP redirect handling vulnerability that fails to remove the HTTP request body when a POST changes to a GET via 301, 302, or 303 responses. This flaw can expose sensitive request data if the origin service is compromised and redirects to a malicious endpoint, though exploitability is low when no sensitive data is used. The vulnerability affects automatic redirect behavior. It is fixed in versions 1.26.18 and 2.0.7; update or disable redirects using redirects=False.
This vulnerability is specific to Python's urllib3 library.

urllib3 is a user-friendly HTTP client library for Python. Prior to 2.5.0, it is possible to disable redirects for all requests by instantiating a PoolManager and specifying retries in a way that disable redirects. By default, requests and botocore users are not affected. An application attempting to mitigate SSRF or open redirect vulnerabilities by disabling redirects at the PoolManager level will remain vulnerable. This issue has been patched in version 2.5.0.

Urllib3 1.25.9 includes a fix for CVE-2020-26137: Urllib3 before 1.25.9 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserting CR and LF control characters in the first argument of putrequest(). NOTE: this is similar to CVE-2020-26116.
https://github.com/python/cpython/issues/83784
https://github.com/urllib3/urllib3/pull/1800

Affected versions of the gunicorn package are vulnerable to HTTP Request/Response Smuggling due to improper validation of the Transfer-Encoding header that enables a TE.CL desynchronisation condition. Gunicorn’s HTTP parser does not consistently enforce RFC semantics when parsing conflicting or unsupported request framing—such as messages containing both Transfer-Encoding and Content-Length—so the backend may fall back to Content-Length while an intermediary treats the message as chunked.

Gunicorn 20.0.1 fixes chunked encoding support to prevent http request smuggling attacks.
https://github.com/benoitc/gunicorn/issues/2176
https://github.com/p4k03n4t0r/http-request-smuggling#request-smuggling-using-mitmproxy-and-gunicorn

Gunicorn fails to properly validate Transfer-Encoding headers, leading to HTTP Request Smuggling (HRS) vulnerabilities. By crafting requests with conflicting Transfer-Encoding headers, attackers can bypass security restrictions and access restricted endpoints. This issue is due to Gunicorn's handling of Transfer-Encoding headers, where it incorrectly processes requests with multiple, conflicting Transfer-Encoding headers, treating them as chunked regardless of the final encoding specified. This vulnerability allows for a range of attacks including cache poisoning, session manipulation, and data exposure.

Requests is an HTTP library. Due to a URL parsing issue, Requests releases prior to 2.32.4 may leak .netrc credentials to third parties for specific maliciously-crafted URLs. Users should upgrade to version 2.32.4 to receive a fix. For older versions of Requests, use of the .netrc file can be disabled with `trust_env=False` on one's Requests Session.

Affected versions of Requests are vulnerable to proxy credential leakage. When redirected to an HTTPS endpoint, the Proxy-Authorization header is forwarded to the destination server due to the use of rebuild_proxies to reattach the header. This may allow a malicious actor to exfiltrate sensitive information.

Affected versions of the requests package are vulnerable to Insecure Temporary File reuse due to predictable temporary filename generation in extract_zipped_paths(). The requests.utils.extract_zipped_paths() utility extracts files from zip archives into the system temporary directory using a deterministic path, and if that file already exists, the function reuses it without validating that it is the expected extracted content.

Affected versions of Requests, when making requests through a Requests `Session`, if the first request is made with `verify=False` to disable cert verification, all subsequent requests to the same host will continue to ignore cert verification regardless of changes to the value of `verify`. This behavior will continue for the lifecycle of the connection in the connection pool. Requests 2.32.0 fixes the issue, but versions 2.32.0 and 2.32.1 were yanked due to conflicts with CVE-2024-35195 mitigation.

Certifi 2022.12.07 includes a fix for CVE-2022-23491: Certifi 2022.12.07 removes root certificates from "TrustCor" from the root store. These are in the process of being removed from Mozilla's trust store. TrustCor's root certificates are being removed pursuant to an investigation prompted by media reporting that TrustCor's ownership also operated a business that produced spyware. Conclusions of Mozilla's investigation can be found in the linked google group discussion.

Certifi 2023.07.22 includes a fix for CVE-2023-37920: Certifi prior to version 2023.07.22 recognizes "e-Tugra" root certificates. e-Tugra's root certificates were subject to an investigation prompted by reporting of security issues in their systems. Certifi 2023.07.22 removes root certificates from "e-Tugra" from the root store.
https://github.com/certifi/python-certifi/security/advisories/GHSA-xqr8-7jwr-rhp7

Certifi 2022.12.07 includes a fix for CVE-2022-23491: Certifi 2022.12.07 removes root certificates from "TrustCor" from the root store. These are in the process of being removed from Mozilla's trust store. TrustCor's root certificates are being removed pursuant to an investigation prompted by media reporting that TrustCor's ownership also operated a business that produced spyware. Conclusions of Mozilla's investigation can be found in the linked google group discussion.

Certifi 2023.07.22 includes a fix for CVE-2023-37920: Certifi prior to version 2023.07.22 recognizes "e-Tugra" root certificates. e-Tugra's root certificates were subject to an investigation prompted by reporting of security issues in their systems. Certifi 2023.07.22 removes root certificates from "e-Tugra" from the root store.
https://github.com/certifi/python-certifi/security/advisories/GHSA-xqr8-7jwr-rhp7

Affected versions of Sentry's Python SDK are vulnerable to unintentional exposure of environment variables to subprocesses despite the env={} setting. In Python's 'subprocess' calls, all environment variables are passed to subprocesses by default. However, if you specifically do not want them to be passed to subprocesses, you may use 'env' argument in 'subprocess' calls. Due to the bug in Sentry SDK, with the Stdlib integration enabled (which is enabled by default), this expectation is not fulfilled, and all environment variables are being passed to subprocesses instead. 
As a workaround, and if passing environment variables to child processes poses a security risk for you, you can disable all default integrations.

Sentry-sdk 1.14.0 includes a fix for CVE-2023-28117: When using the Django integration of versions prior to 1.14.0 of the Sentry SDK in a specific configuration it is possible to leak sensitive cookies values, including the session cookie to Sentry. These sensitive cookies could then be used by someone with access to your Sentry issues to impersonate or escalate their privileges within your application. In order for these sensitive values to be leaked, the Sentry SDK configuration must have 'sendDefaultPII' set to 'True'; one must use a custom name for either 'SESSION_COOKIE_NAME' or 'CSRF_COOKIE_NAME' in one's Django settings; and one must not be configured in one's organization or project settings to use Sentry's data scrubbing features to account for the custom cookie names. As of version 1.14.0, the Django integration of the 'sentry-sdk' will detect the custom cookie names based on one's Django settings and will remove the values from the payload before sending the data to Sentry. As a workaround, use the SDK's filtering mechanism to remove the cookies from the payload that is sent to Sentry. For error events, this can be done with the 'before_send' callback method and for performance related events (transactions) one can use the 'before_send_transaction' callback method. Those who want to handle filtering of these values on the server-side can also use Sentry's advanced data scrubbing feature to account for the custom cookie names. Look for the '$http.cookies', '$http.headers', '$request.cookies', or '$request.headers' fields to target with a scrubbing rule.
https://github.com/getsentry/sentry-python/security/advisories/GHSA-29pr-6jr8-q5jm

Sentry-sdk 1.4.1 includes a fix for a Race Condition vulnerability.
https://github.com/getsentry/sentry-python/pull/1203

A SQL Injection issue in the SQL Panel in Jazzband Django Debug Toolbar before 1.11.1, 2.x before 2.2.1, and 3.x before 3.2.1 allows attackers to execute SQL statements by changing the raw_sql input field of the SQL explain, analyze, or select form. See CVE-2021-30459.

** DISPUTED ** Py throughout 1.11.0 allows remote attackers to conduct a ReDoS (Regular expression Denial of Service) attack via a Subversion repository with crafted info data because the InfoSvnCommand argument is mishandled.
https://github.com/pytest-dev/py/issues/287

Py 1.10.0 includes a fix for CVE-2020-29651: A denial of service via regular expression in the py.path.svnwc component of py (aka python-py) through 1.9.0 could be used by attackers to cause a compute-time denial of service attack by supplying malicious input to the blame functionality.

Affected versions of Idna are vulnerable to Denial Of Service via the idna.encode(), where a specially crafted argument could lead to significant resource consumption. In version 3.7, this function has been updated to reject such inputs efficiently, minimizing resource use. A practical workaround involves enforcing a maximum domain name length of 253 characters before encoding, as the vulnerability is triggered by unusually large inputs that normal operations wouldn't encounter.

** DISPUTED ** Py throughout 1.11.0 allows remote attackers to conduct a ReDoS (Regular expression Denial of Service) attack via a Subversion repository with crafted info data because the InfoSvnCommand argument is mishandled.
https://github.com/pytest-dev/py/issues/287

Py 1.10.0 includes a fix for CVE-2020-29651: A denial of service via regular expression in the py.path.svnwc component of py (aka python-py) through 1.9.0 could be used by attackers to cause a compute-time denial of service attack by supplying malicious input to the blame functionality.

An issue was discovered in Django 2.2 before 2.2.13 and 3.0 before 3.0.7. Query parameters generated by the Django admin ForeignKeyRawIdWidget were not properly URL encoded, leading to a possibility of an XSS attack.

Affected versions of the Django package are vulnerable to SQL Injection due to improper handling of control characters in column aliases within FilteredRelation. The FilteredRelation class fails to properly sanitize column aliases containing control characters when used with QuerySet methods annotate(), aggregate(), extra(), values(), values_list(), and alias() via dictionary expansion (**kwargs).

Affected versions of the Django package are vulnerable to SQL Injection due to improper sanitization of band index parameters in PostGIS raster lookups. The raster lookup functionality in Django's GIS module fails to properly validate or escape untrusted data used as a band index when performing spatial queries against PostGIS databases.

Affected versions of Django are vulnerable to potential denial-of-service in intcomma template filter when used with very long strings.

A potential denial-of-service vulnerability has been identified in Django's urlize() and urlizetrunc() functions in django.utils.html. This vulnerability can be triggered by inputting huge strings containing a specific sequence of characters.

Django 3.2.14 and 4.0.6 include a fix for CVE-2022-34265: Potential SQL injection via Trunc(kind) and Extract(lookup_name) arguments.
https://www.djangoproject.com/weblog/2022/jul/04/security-releases

An issue was discovered in Django 2.2 before 2.2.13 and 3.0 before 3.0.7. In cases where a memcached backend does not perform key validation, passing malformed cache keys could result in a key collision, and potential data leakage.

Django 4.1.7, 4.0.10 and 3.2.18 include a fix for CVE-2023-24580: Potential denial-of-service vulnerability in file uploads.
https://www.djangoproject.com/weblog/2023/feb/14/security-releases

An issue was discovered in Django 2.2 before 2.2.16, 3.0 before 3.0.10, and 3.1 before 3.1.1 (when Python 3.7+ is used). The intermediate-level directories of the filesystem cache had the system's standard umask rather than 0o077.

Django versions 3.2.2, 3.1.10 and 2.2.22 include a fix for CVE-2021-32052: In Django 2.2 before 2.2.22, 3.1 before 3.1.10, and 3.2 before 3.2.2 (with Python 3.9.5+), URLValidator does not prohibit newlines and tabs (unless the URLField form field is used). If an application uses values with newlines in an HTTP response, header injection can occur. Django itself is unaffected because HttpResponse prohibits newlines in HTTP headers.
https://www.djangoproject.com/weblog/2021/may/06/security-releases

Affected versions of the Django package are vulnerable to Path Traversal due to improper validation of file paths in the django.contrib.admindocs module. The `TemplateDetailView` view allows staff members to verify the existence of arbitrary files by manipulating the file path. An attacker with staff privileges can exploit this vulnerability to check for the presence of files outside the template root directories, and if the `admindocs` templates are customized to display file contents, they can also access the contents of these files.

Django addresses a memory exhaustion issue in django.utils.numberformat.floatformat(). When floatformat receives a string representation of a number in scientific notation with a large exponent, it could lead to excessive memory consumption. To prevent this, decimals with more than 200 digits are now returned as-is.

Django 2.2.24, 3.1.12, and 3.2.4 include a fix for CVE-2021-33571: In Django 2.2 before 2.2.24, 3.x before 3.1.12, and 3.2 before 3.2.4, URLValidator, validate_ipv4_address, and validate_ipv46_address do not prohibit leading zero characters in octal literals. This may allow a bypass of access control that is based on IP addresses. (validate_ipv4_address and validate_ipv46_address are unaffected with Python 3.9.5+).
https://www.djangoproject.com/weblog/2021/jun/02/security-releases

Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to inefficient string concatenation when processing duplicate HTTP headers in ASGI mode. The ASGIRequest class combines repeated headers using repeated string concatenation, resulting in super-linear (quadratic) time complexity when processing requests with many duplicate headers.

Affected versions of the Django package are vulnerable to SQL Injection due to improper handling of column aliases containing periods in QuerySet.order_by() when combined with FilteredRelation. The QuerySet.order_by() method fails to properly sanitize column aliases that contain periods when the same alias is used in FilteredRelation via dictionary expansion. 
https://github.com/django/django/commit/90f5b10784ba5bf369caed87640e2b4394ea3314

Django 2.2.21, 3.1.9 and 3.2.1 include a fix for CVE-2021-31542: MultiPartParser, UploadedFile, and FieldFile allowed directory traversal via uploaded files with suitably crafted file names.
https://www.djangoproject.com/weblog/2021/may/04/security-releases

An issue was discovered in Django 4.2 before 4.2.21, 5.1 before 5.1.9, and 5.2 before 5.2.1. The django.utils.html.strip_tags() function is vulnerable to a potential denial-of-service (slow performance) when processing inputs containing large sequences of incomplete HTML tags. The template filter striptags is also vulnerable, because it is built on top of strip_tags().

In Django 3.2 before 3.2.16, 4.0 before 4.0.8, and 4.1 before 4.1.2, internationalized URLs were subject to a potential denial of service attack via the locale parameter, which is treated as a regular expression.

Affected versions of Django are vulnerable to potential Denial of Service via certain inputs with a very large number of Unicode characters in django.utils.encoding.uri_to_iri().

Django 1.11.29, 2.2.11 and 3.0.4 includes a fix for CVE-2020-9402: Django 1.11 before 1.11.29, 2.2 before 2.2.11, and 3.0 before 3.0.4 allows SQL Injection if untrusted data is used as a tolerance parameter in GIS functions and aggregates on Oracle. By passing a suitably crafted tolerance to GIS functions and aggregates on Oracle, it was possible to break escaping and inject malicious SQL.
https://www.djangoproject.com/weblog/2020/mar/04/security-releases

Django affected versions are vulnerable to a potential SQL injection in the HasKey(lhs, rhs) lookup on Oracle databases. The vulnerability arises when untrusted data is directly used as the lhs value in the django.db.models.fields.json.HasKey lookup. However, applications using the jsonfield.has_key lookup with the __ syntax remain unaffected by this issue.

Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to quadratic time complexity during HTML parsing in text truncation methods. The django.utils.text.Truncator.chars() and Truncator.words() methods (with html=True), as well as the truncatechars_html and truncatewords_html template filters, exhibit quadratic time complexity when processing inputs containing a large number of unmatched HTML end tags.

Django versions 2.2.25, 3.1.14 and 3.2.10 include a fix for CVE-2021-44420: In Django 2.2 before 2.2.25, 3.1 before 3.1.14, and 3.2 before 3.2.10, HTTP requests for URLs with trailing newlines could bypass upstream access control based on URL paths.
https://www.djangoproject.com/weblog/2021/dec/07/security-releases/

Django 2.1.15 and 2.2.8 includes a fix for CVE-2019-19118: A Django model admin displaying inline related models, where the user has view-only permissions to a parent model but edit permissions to the inline model, would be presented with an editing UI, allowing POST requests, for updating the inline model. Directly editing the view-only parent model was not possible, but the parent model's save() method was called, triggering potential side effects, and causing pre and post-save signal handlers to be invoked. To resolve this, the Django admin is adjusted to require edit permissions on the parent model in order for inline models to be editable.

Django 1.11.27, 2.2.9 and 3.0.1 include a fix for CVE-2019-19844: Account takeover. A suitably crafted email address (that is equal to an existing user's email address after case transformation of Unicode characters) would allow an attacker to be sent a password reset token for the matched user account. One mitigation in the new releases is to send password reset tokens only to the registered user email address.

Django has a potential denial-of-service vulnerability in django.utils.html.urlize() and AdminURLFieldWidget. The urlize and urlizetrunc functions, along with AdminURLFieldWidget, are vulnerable to denial-of-service attacks when handling inputs with a very large number of Unicode characters.

Affected versions of Django are potentially vulnerable to denial-of-service via the get_supported_language_variant() method. This method was susceptible to a denial-of-service attack when used with very long strings containing specific characters. Exploiting this vulnerability could cause significant delays or crashes in the affected application, potentially leading to service disruption.

Django versions 2.2.19, 3.0.13 and 3.1.7 include a fix for CVE-2021-23336: Web cache poisoning via 'django.utils.http.limited_parse_qsl()'. Django contains a copy of 'urllib.parse.parse_qsl' which was added to backport some security fixes. A further security fix has been issued recently such that 'parse_qsl(' no longer allows using ';' as a query parameter separator by default.

Django 4.2.1, 4.1.9 and 3.2.19 include a fix for CVE-2023-31047: In Django 3.2 before 3.2.19, 4.x before 4.1.9, and 4.2 before 4.2.1, it was possible to bypass validation when using one form field to upload multiple files. This multiple upload has never been supported by forms.FileField or forms.ImageField (only the last uploaded file was validated). However, Django's "Uploading multiple files" documentation suggested otherwise.
https://www.djangoproject.com/weblog/2023/may/03/security-releases

Affected versions of Django are vulnerable to potential regular expression denial-of-service (REDoS). django.utils.text.Truncator.words() method (with html=True) and truncatewords_html template filter were subject to a potential regular expression denial-of-service attack using a suitably crafted string (follow up to CVE-2019-14232 and CVE-2023-43665).

Affected versions of Django are vulnerable to a potential ReDoS (regular expression denial of service) in EmailValidator and URLValidator via a very large number of domain name labels of emails and URLs.

Django 2.2.27, 3.2.12 and 4.0.2 include a fix for CVE-2022-23833: Denial-of-service possibility in file uploads.
https://www.djangoproject.com/weblog/2022/feb/01/security-releases

Django 2.2.28, 3.2.13 and 4.0.4 include a fix for CVE-2022-28346: An issue was discovered in Django 2.2 before 2.2.28, 3.2 before 3.2.13, and 4.0 before 4.0.4. QuerySet.annotate(), aggregate(), and extra() methods are subject to SQL injection in column aliases via a crafted dictionary (with dictionary expansion) as the passed **kwargs.
https://www.djangoproject.com/weblog/2022/apr/11/security-releases

In Django 2.2 before 2.2.20, 3.0 before 3.0.14, and 3.1 before 3.1.8, MultiPartParser allowed directory traversal via uploaded files with suitably crafted file names. Built-in upload handlers were not affected by this vulnerability.

CVE-2025-64458: Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to slow Unicode NFKC normalization on Windows being applied to untrusted inputs. The django.contrib.auth.views.LoginView and django.contrib.auth.views.LogoutView, and django.views.i18n.set_language normalize user-controlled strings using Python’s NFKC algorithm, which is unusually slow on Windows for huge Unicode sequences and can be triggered to consume excessive CPU.

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45452: Storage.save in Django 2.2 before 2.2.26, 3.2 before 3.2.11, and 4.0 before 4.0.1 allows directory traversal if crafted filenames are directly passed to it.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases/

Affected versions of Django are vulnerable to a potential denial-of-service (DoS) attack in the `django.utils.html.strip_tags()` method. The vulnerability occurs when the `strip_tags()` method or the `striptags` template filter processes inputs containing large sequences of nested, incomplete HTML entities.

Affected versions of the Django package are vulnerable to Information Disclosure (Timing Attack) due to non-constant-time comparison in the mod_wsgi authentication handler. The django.contrib.auth.handlers.modwsgi.check_password() function does not perform user existence checks in constant time, allowing response timing differences to reveal whether usernames exist.

The {% debug %} template tag in Django 2.2 before 2.2.27, 3.2 before 3.2.12, and 4.0 before 4.0.2 does not properly encode the current context. This may lead to XSS.

Django fixes a potential denial-of-service vulnerability in XML ``Deserializer``.

An issue was discovered in Django 5.2 before 5.2.3, 5.1 before 5.1.11, and 4.2 before 4.2.23. Internal HTTP response logging does not escape request.path, which allows remote attackers to potentially manipulate log output via crafted URLs. This may lead to log injection or forgery when logs are viewed in terminals or processed by external systems.

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45116: An issue was discovered in Django 2.2 before 2.2.26, 3.2 before 3.2.11, and 4.0 before 4.0.1. Due to leveraging the Django Template Language's variable resolution logic, the dictsort template filter was potentially vulnerable to information disclosure, or an unintended method call, if passed a suitably crafted key.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45115: UserAttributeSimilarityValidator incurred significant overhead in evaluating a submitted password that was artificially large in relation to the comparison values. In a situation where access to user registration was unrestricted, this provided a potential vector for a denial-of-service attack.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases/

Affected versions of Django are affected by a potential denial-of-service vulnerability in the django.utils.html.urlize() function. The urlize and urlizetrunc template filters were susceptible to a denial-of-service attack via certain inputs containing many brackets. An attacker could exploit this vulnerability to cause significant delays or crashes in the affected application.

Affected versions of Django are affected by a directory-traversal vulnerability in the Storage.save() method. Derived classes of the django.core.files.storage.Storage base class that overrides the generate_filename() method without replicating the file path validations existing in the parent class could allow for directory traversal via certain inputs when calling save(). This could enable an attacker to manipulate file paths and access unintended directories.

Django 1.11.28, 2.2.10 and 3.0.3 include a fix for CVE-2020-7471: SQL Injection if untrusted data is used as a StringAgg delimiter (e.g., in Django applications that offer downloads of data as a series of rows with a user-specified column delimiter). By passing a suitably crafted delimiter to a contrib.postgres.aggregates.StringAgg instance, it was possible to break escaping and inject malicious SQL.

Affected versions of Django has a potential SQL injection vulnerability in the QuerySet.values() and QuerySet.values_list() methods. When used on models with a JSONField, these methods are susceptible to SQL injection through column aliases if a crafted JSON object key is passed as an argument.

A security vulnerability has been discovered in certain versions of Django, affecting the password reset functionality. The PasswordResetForm class in django.contrib.auth.forms inadvertently allowed attackers to enumerate user email addresses by exploiting unhandled exceptions during the email sending process. This could be done by issuing password reset requests and observing the responses. Django has implemented a fix where these exceptions are now caught and logged using the django.contrib.auth logger, preventing potential information leakage through error responses.

Django 2.2.18, 3.0.12 and 3.1.6 include a fix for CVE-2021-3281: The django.utils.archive.extract method (used by "startapp --template" and "startproject --template") allows directory traversal via an archive with absolute paths or relative paths with dot segments.

Django 4.2.7, 4.1.13 and 3.2.23 include a fix for CVE-2023-46695: Potential denial of service vulnerability in UsernameField on Windows.
https://www.djangoproject.com/weblog/2023/nov/01/security-releases

Affected versions of Django are vulnerable to Denial-of-Service via django.utils.text.Truncator. The django.utils.text.Truncator chars() and words() methods (when used with html=True) are subject to a potential DoS (denial of service) attack via certain inputs with very long, potentially malformed HTML text. The chars() and words() methods are used to implement the truncatechars_html and truncatewords_html template filters, which are thus also vulnerable. NOTE: this issue exists because of an incomplete fix for CVE-2019-14232.

Affected versions of Django are affected by a username enumeration vulnerability caused by timing differences in the django.contrib.auth.backends.ModelBackend.authenticate() method. This method allowed remote attackers to enumerate users through a timing attack involving login requests for users with unusable passwords. The timing difference in the authentication process exposed whether a username was valid or not, potentially aiding attackers in gaining unauthorized access.

Django 2.2.28, 3.2.13 and 4.0.4 include a fix for CVE-2022-28347: A SQL injection issue was discovered in QuerySet.explain() in Django 2.2 before 2.2.28, 3.2 before 3.2.13, and 4.0 before 4.0.4. This occurs by passing a crafted dictionary (with dictionary expansion) as the **options argument, and placing the injection payload in an option name.
https://www.djangoproject.com/weblog/2022/apr/11/security-releases

Django 2.2.16, 3.0.10 and 3.1.1 include a fix for CVE-2020-24583: An issue was discovered in Django 2.2 before 2.2.16, 3.0 before 3.0.10, and 3.1 before 3.1.1 (when Python 3.7+ is used). FILE_UPLOAD_DIRECTORY_PERMISSIONS mode was not applied to intermediate-level directories created in the process of uploading files. It was also not applied to intermediate-level collected static directories when using the collectstatic management command.
#NOTE: This vulnerability affects only users of Python versions above 3.7.
https://www.djangoproject.com/weblog/2020/sep/01/security-releases

Django 3.2.17, 4.0.9 and 4.1.6 includes a fix for CVE-2023-23969: In Django 3.2 before 3.2.17, 4.0 before 4.0.9, and 4.1 before 4.1.6, the parsed values of Accept-Language headers are cached in order to avoid repetitive parsing. This leads to a potential denial-of-service vector via excessive memory usage if the raw value of Accept-Language headers is very large.
https://www.djangoproject.com/weblog/2023/feb/01/security-releases

Affected versions of the `django` package are vulnerable to Download of Code Without Integrity Check due to improper handling of user-supplied input in the HTTP FileResponse class. The vulnerability arises because the Content-Disposition header of a FileResponse can be set using a filename derived from user input without sufficient validation. An attacker can exploit this by crafting a request that causes a file with malicious content to be downloaded, potentially executing arbitrary code on the client system when the file is opened.

CVE-2025-64459: Affected versions of the Django package are vulnerable to SQL Injection due to improper input validation, allowing the internal _connector keyword argument to be accepted from untrusted dictionaries via expansion. The .filter(), .exclude(), and .get() methods on QuerySet, as well as the Q class, resolve **kwargs and will treat a supplied _connector value as the logical connector without constraining it to the expected set (AND/OR), permitting attacker-controlled tokens to influence SQL predicate construction.

Affected versions of the Django package are vulnerable to SQL Injection due to insufficient input sanitization in FilteredRelation column aliases. The FilteredRelation class fails to properly validate or escape column alias names when they are provided through dictionary expansion as keyword arguments to QuerySet.annotate() or QuerySet.alias() methods, allowing malicious SQL code to be injected directly into the generated database queries.

Django fixes potential SQL injection in ``FilteredRelation`` column aliases on PostgreSQL.

Affected versions of the sqlparse package are vulnerable to Denial of Service (DoS) due to missing hard limits on token grouping recursion depth and token processing when formatting very large SQL tuple lists. During sqlparse.format() processing, the sqlparse.engine.grouping._group_matching() and sqlparse.engine.grouping._group() functions can recurse and iterate over excessively large tlist.tokens without enforcing MAX_GROUPING_DEPTH or MAX_GROUPING_TOKENS, allowing grouping work to grow until it effectively hangs.

Affected versions of this package are vulnerable to Denial of Service (DoS) attacks due to Algorithmic Complexity. The SQL parser fails to enforce limits when processing deeply nested tuples and large token sequences, leading to excessive resource consumption through crafted SQL statements with extreme nesting depth or token counts.

**Note:** This issue is due to an incomplete fix for CVE-2024-4340.

Sqlparse 0.5.0 addresses a potential denial of service (DoS) vulnerability related to recursion errors in deeply nested SQL statements. To mitigate this issue, the update replaces recursion errors with a general SQLParseError, improving the resilience and stability of the parsing process.

Sqlparse 0.4.4 includes a fix for CVE-2023-30608: Parser contains a regular expression that is vulnerable to ReDOS (Regular Expression Denial of Service).
https://github.com/andialbrecht/sqlparse/security/advisories/GHSA-rrm6-wvj7-cwh2

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to redirect handling that drains connections by decompressing redirect response bodies without enforcing streaming read limits. The issue occurs when using urllib3’s streaming mode (for example, preload_content=False) while allowing redirects, because urllib3.response.HTTPResponse.drain_conn() would call HTTPResponse.read() in a way that decoded/decompressed the entire redirect response body even before any streaming reads were performed, effectively bypassing decompression-bomb safeguards.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to improper handling of highly compressed HTTP response bodies during streaming decompression. The urllib3.HTTPResponse methods stream(), read(), read1(), read_chunked(), and readinto() may fully decompress a minimal but highly compressed payload based on the Content-Encoding header into an internal buffer instead of limiting the decompressed output to the requested chunk size, causing excessive CPU usage and massive memory allocation on the client side.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to allowing an unbounded number of content-encoding decompression steps for HTTP responses. The HTTPResponse content decoding pipeline in urllib3 follows the Content-Encoding header and applies each advertised compression algorithm in sequence without enforcing a maximum chain length or effective output size, so a malicious peer can send a response with a very long encoding chain that triggers excessive CPU use and massive memory allocation during decompression.

Urllib3's ProxyManager ensures that the Proxy-Authorization header is correctly directed only to configured proxies. However, when HTTP requests bypass urllib3's proxy support, there's a risk of inadvertently setting the Proxy-Authorization header, which remains ineffective without a forwarding or tunneling proxy. Urllib3 does not recognize this header as carrying authentication data, failing to remove it during cross-origin redirects. While this scenario is uncommon and poses low risk to most users, urllib3 now proactively removes the Proxy-Authorization header during cross-origin redirects as a precautionary measure. Users are advised to utilize urllib3's proxy support or disable automatic redirects to handle the Proxy-Authorization header securely. Despite these precautions, urllib3 defaults to stripping the header to safeguard users who may inadvertently misconfigure requests.

Urllib3 1.26.17 and 2.0.5 include a fix for CVE-2023-43804: Urllib3 doesn't treat the 'Cookie' HTTP header special or provide any helpers for managing cookies over HTTP, that is the responsibility of the user. However, it is possible for a user to specify a 'Cookie' header and unknowingly leak information via HTTP redirects to a different origin if that user doesn't disable redirects explicitly.
https://github.com/urllib3/urllib3/security/advisories/GHSA-v845-jxx5-vc9f

Urllib3 1.26.5 includes a fix for CVE-2021-33503: When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking, causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redirect.
https://github.com/advisories/GHSA-q2q7-5pp4-w6pg

The _encode_invalid_chars function in util/url.py in the urllib3 library 1.25.2 through 1.25.7 for Python allows a denial of service (CPU consumption) because of an inefficient algorithm. The percent_encodings array contains all matches of percent encodings. It is not deduplicated. For a URL of length N, the size of percent_encodings may be up to O(N). The next step (normalize existing percent-encoded bytes) also takes up to O(N) for each step, so the total time is O(N^2). If percent_encodings were deduplicated, the time to compute _encode_invalid_chars would be O(kN), where k is at most 484 ((10+6*2)^2). See: CVE-2020-7212.

Affected versions of urllib3 are vulnerable to an HTTP redirect handling vulnerability that fails to remove the HTTP request body when a POST changes to a GET via 301, 302, or 303 responses. This flaw can expose sensitive request data if the origin service is compromised and redirects to a malicious endpoint, though exploitability is low when no sensitive data is used. The vulnerability affects automatic redirect behavior. It is fixed in versions 1.26.18 and 2.0.7; update or disable redirects using redirects=False.
This vulnerability is specific to Python's urllib3 library.

urllib3 is a user-friendly HTTP client library for Python. Prior to 2.5.0, it is possible to disable redirects for all requests by instantiating a PoolManager and specifying retries in a way that disable redirects. By default, requests and botocore users are not affected. An application attempting to mitigate SSRF or open redirect vulnerabilities by disabling redirects at the PoolManager level will remain vulnerable. This issue has been patched in version 2.5.0.

Urllib3 1.25.9 includes a fix for CVE-2020-26137: Urllib3 before 1.25.9 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserting CR and LF control characters in the first argument of putrequest(). NOTE: this is similar to CVE-2020-26116.
https://github.com/python/cpython/issues/83784
https://github.com/urllib3/urllib3/pull/1800

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to redirect handling that drains connections by decompressing redirect response bodies without enforcing streaming read limits. The issue occurs when using urllib3’s streaming mode (for example, preload_content=False) while allowing redirects, because urllib3.response.HTTPResponse.drain_conn() would call HTTPResponse.read() in a way that decoded/decompressed the entire redirect response body even before any streaming reads were performed, effectively bypassing decompression-bomb safeguards.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to improper handling of highly compressed HTTP response bodies during streaming decompression. The urllib3.HTTPResponse methods stream(), read(), read1(), read_chunked(), and readinto() may fully decompress a minimal but highly compressed payload based on the Content-Encoding header into an internal buffer instead of limiting the decompressed output to the requested chunk size, causing excessive CPU usage and massive memory allocation on the client side.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to allowing an unbounded number of content-encoding decompression steps for HTTP responses. The HTTPResponse content decoding pipeline in urllib3 follows the Content-Encoding header and applies each advertised compression algorithm in sequence without enforcing a maximum chain length or effective output size, so a malicious peer can send a response with a very long encoding chain that triggers excessive CPU use and massive memory allocation during decompression.

Urllib3's ProxyManager ensures that the Proxy-Authorization header is correctly directed only to configured proxies. However, when HTTP requests bypass urllib3's proxy support, there's a risk of inadvertently setting the Proxy-Authorization header, which remains ineffective without a forwarding or tunneling proxy. Urllib3 does not recognize this header as carrying authentication data, failing to remove it during cross-origin redirects. While this scenario is uncommon and poses low risk to most users, urllib3 now proactively removes the Proxy-Authorization header during cross-origin redirects as a precautionary measure. Users are advised to utilize urllib3's proxy support or disable automatic redirects to handle the Proxy-Authorization header securely. Despite these precautions, urllib3 defaults to stripping the header to safeguard users who may inadvertently misconfigure requests.

Urllib3 1.26.17 and 2.0.5 include a fix for CVE-2023-43804: Urllib3 doesn't treat the 'Cookie' HTTP header special or provide any helpers for managing cookies over HTTP, that is the responsibility of the user. However, it is possible for a user to specify a 'Cookie' header and unknowingly leak information via HTTP redirects to a different origin if that user doesn't disable redirects explicitly.
https://github.com/urllib3/urllib3/security/advisories/GHSA-v845-jxx5-vc9f

Urllib3 1.26.5 includes a fix for CVE-2021-33503: When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking, causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redirect.
https://github.com/advisories/GHSA-q2q7-5pp4-w6pg

The _encode_invalid_chars function in util/url.py in the urllib3 library 1.25.2 through 1.25.7 for Python allows a denial of service (CPU consumption) because of an inefficient algorithm. The percent_encodings array contains all matches of percent encodings. It is not deduplicated. For a URL of length N, the size of percent_encodings may be up to O(N). The next step (normalize existing percent-encoded bytes) also takes up to O(N) for each step, so the total time is O(N^2). If percent_encodings were deduplicated, the time to compute _encode_invalid_chars would be O(kN), where k is at most 484 ((10+6*2)^2). See: CVE-2020-7212.

Affected versions of urllib3 are vulnerable to an HTTP redirect handling vulnerability that fails to remove the HTTP request body when a POST changes to a GET via 301, 302, or 303 responses. This flaw can expose sensitive request data if the origin service is compromised and redirects to a malicious endpoint, though exploitability is low when no sensitive data is used. The vulnerability affects automatic redirect behavior. It is fixed in versions 1.26.18 and 2.0.7; update or disable redirects using redirects=False.
This vulnerability is specific to Python's urllib3 library.

urllib3 is a user-friendly HTTP client library for Python. Prior to 2.5.0, it is possible to disable redirects for all requests by instantiating a PoolManager and specifying retries in a way that disable redirects. By default, requests and botocore users are not affected. An application attempting to mitigate SSRF or open redirect vulnerabilities by disabling redirects at the PoolManager level will remain vulnerable. This issue has been patched in version 2.5.0.

Urllib3 1.25.9 includes a fix for CVE-2020-26137: Urllib3 before 1.25.9 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserting CR and LF control characters in the first argument of putrequest(). NOTE: this is similar to CVE-2020-26116.
https://github.com/python/cpython/issues/83784
https://github.com/urllib3/urllib3/pull/1800

Affected versions of the gunicorn package are vulnerable to HTTP Request/Response Smuggling due to improper validation of the Transfer-Encoding header that enables a TE.CL desynchronisation condition. Gunicorn’s HTTP parser does not consistently enforce RFC semantics when parsing conflicting or unsupported request framing—such as messages containing both Transfer-Encoding and Content-Length—so the backend may fall back to Content-Length while an intermediary treats the message as chunked.

Gunicorn 20.0.1 fixes chunked encoding support to prevent http request smuggling attacks.
https://github.com/benoitc/gunicorn/issues/2176
https://github.com/p4k03n4t0r/http-request-smuggling#request-smuggling-using-mitmproxy-and-gunicorn

Gunicorn fails to properly validate Transfer-Encoding headers, leading to HTTP Request Smuggling (HRS) vulnerabilities. By crafting requests with conflicting Transfer-Encoding headers, attackers can bypass security restrictions and access restricted endpoints. This issue is due to Gunicorn's handling of Transfer-Encoding headers, where it incorrectly processes requests with multiple, conflicting Transfer-Encoding headers, treating them as chunked regardless of the final encoding specified. This vulnerability allows for a range of attacks including cache poisoning, session manipulation, and data exposure.

Requests is an HTTP library. Due to a URL parsing issue, Requests releases prior to 2.32.4 may leak .netrc credentials to third parties for specific maliciously-crafted URLs. Users should upgrade to version 2.32.4 to receive a fix. For older versions of Requests, use of the .netrc file can be disabled with `trust_env=False` on one's Requests Session.

Affected versions of Requests are vulnerable to proxy credential leakage. When redirected to an HTTPS endpoint, the Proxy-Authorization header is forwarded to the destination server due to the use of rebuild_proxies to reattach the header. This may allow a malicious actor to exfiltrate sensitive information.

Affected versions of the requests package are vulnerable to Insecure Temporary File reuse due to predictable temporary filename generation in extract_zipped_paths(). The requests.utils.extract_zipped_paths() utility extracts files from zip archives into the system temporary directory using a deterministic path, and if that file already exists, the function reuses it without validating that it is the expected extracted content.

Affected versions of Requests, when making requests through a Requests `Session`, if the first request is made with `verify=False` to disable cert verification, all subsequent requests to the same host will continue to ignore cert verification regardless of changes to the value of `verify`. This behavior will continue for the lifecycle of the connection in the connection pool. Requests 2.32.0 fixes the issue, but versions 2.32.0 and 2.32.1 were yanked due to conflicts with CVE-2024-35195 mitigation.

Certifi 2022.12.07 includes a fix for CVE-2022-23491: Certifi 2022.12.07 removes root certificates from "TrustCor" from the root store. These are in the process of being removed from Mozilla's trust store. TrustCor's root certificates are being removed pursuant to an investigation prompted by media reporting that TrustCor's ownership also operated a business that produced spyware. Conclusions of Mozilla's investigation can be found in the linked google group discussion.

Certifi 2023.07.22 includes a fix for CVE-2023-37920: Certifi prior to version 2023.07.22 recognizes "e-Tugra" root certificates. e-Tugra's root certificates were subject to an investigation prompted by reporting of security issues in their systems. Certifi 2023.07.22 removes root certificates from "e-Tugra" from the root store.
https://github.com/certifi/python-certifi/security/advisories/GHSA-xqr8-7jwr-rhp7

Certifi 2022.12.07 includes a fix for CVE-2022-23491: Certifi 2022.12.07 removes root certificates from "TrustCor" from the root store. These are in the process of being removed from Mozilla's trust store. TrustCor's root certificates are being removed pursuant to an investigation prompted by media reporting that TrustCor's ownership also operated a business that produced spyware. Conclusions of Mozilla's investigation can be found in the linked google group discussion.

Certifi 2023.07.22 includes a fix for CVE-2023-37920: Certifi prior to version 2023.07.22 recognizes "e-Tugra" root certificates. e-Tugra's root certificates were subject to an investigation prompted by reporting of security issues in their systems. Certifi 2023.07.22 removes root certificates from "e-Tugra" from the root store.
https://github.com/certifi/python-certifi/security/advisories/GHSA-xqr8-7jwr-rhp7

Affected versions of Sentry's Python SDK are vulnerable to unintentional exposure of environment variables to subprocesses despite the env={} setting. In Python's 'subprocess' calls, all environment variables are passed to subprocesses by default. However, if you specifically do not want them to be passed to subprocesses, you may use 'env' argument in 'subprocess' calls. Due to the bug in Sentry SDK, with the Stdlib integration enabled (which is enabled by default), this expectation is not fulfilled, and all environment variables are being passed to subprocesses instead. 
As a workaround, and if passing environment variables to child processes poses a security risk for you, you can disable all default integrations.

Sentry-sdk 1.14.0 includes a fix for CVE-2023-28117: When using the Django integration of versions prior to 1.14.0 of the Sentry SDK in a specific configuration it is possible to leak sensitive cookies values, including the session cookie to Sentry. These sensitive cookies could then be used by someone with access to your Sentry issues to impersonate or escalate their privileges within your application. In order for these sensitive values to be leaked, the Sentry SDK configuration must have 'sendDefaultPII' set to 'True'; one must use a custom name for either 'SESSION_COOKIE_NAME' or 'CSRF_COOKIE_NAME' in one's Django settings; and one must not be configured in one's organization or project settings to use Sentry's data scrubbing features to account for the custom cookie names. As of version 1.14.0, the Django integration of the 'sentry-sdk' will detect the custom cookie names based on one's Django settings and will remove the values from the payload before sending the data to Sentry. As a workaround, use the SDK's filtering mechanism to remove the cookies from the payload that is sent to Sentry. For error events, this can be done with the 'before_send' callback method and for performance related events (transactions) one can use the 'before_send_transaction' callback method. Those who want to handle filtering of these values on the server-side can also use Sentry's advanced data scrubbing feature to account for the custom cookie names. Look for the '$http.cookies', '$http.headers', '$request.cookies', or '$request.headers' fields to target with a scrubbing rule.
https://github.com/getsentry/sentry-python/security/advisories/GHSA-29pr-6jr8-q5jm

Sentry-sdk 1.4.1 includes a fix for a Race Condition vulnerability.
https://github.com/getsentry/sentry-python/pull/1203

A SQL Injection issue in the SQL Panel in Jazzband Django Debug Toolbar before 1.11.1, 2.x before 2.2.1, and 3.x before 3.2.1 allows attackers to execute SQL statements by changing the raw_sql input field of the SQL explain, analyze, or select form. See CVE-2021-30459.

** DISPUTED ** Py throughout 1.11.0 allows remote attackers to conduct a ReDoS (Regular expression Denial of Service) attack via a Subversion repository with crafted info data because the InfoSvnCommand argument is mishandled.
https://github.com/pytest-dev/py/issues/287

Py 1.10.0 includes a fix for CVE-2020-29651: A denial of service via regular expression in the py.path.svnwc component of py (aka python-py) through 1.9.0 could be used by attackers to cause a compute-time denial of service attack by supplying malicious input to the blame functionality.

Affected versions of Idna are vulnerable to Denial Of Service via the idna.encode(), where a specially crafted argument could lead to significant resource consumption. In version 3.7, this function has been updated to reject such inputs efficiently, minimizing resource use. A practical workaround involves enforcing a maximum domain name length of 253 characters before encoding, as the vulnerability is triggered by unusually large inputs that normal operations wouldn't encounter.

** DISPUTED ** Py throughout 1.11.0 allows remote attackers to conduct a ReDoS (Regular expression Denial of Service) attack via a Subversion repository with crafted info data because the InfoSvnCommand argument is mishandled.
https://github.com/pytest-dev/py/issues/287

Py 1.10.0 includes a fix for CVE-2020-29651: A denial of service via regular expression in the py.path.svnwc component of py (aka python-py) through 1.9.0 could be used by attackers to cause a compute-time denial of service attack by supplying malicious input to the blame functionality.

An issue was discovered in Django 2.2 before 2.2.13 and 3.0 before 3.0.7. Query parameters generated by the Django admin ForeignKeyRawIdWidget were not properly URL encoded, leading to a possibility of an XSS attack.

Affected versions of the Django package are vulnerable to SQL Injection due to improper handling of control characters in column aliases within FilteredRelation. The FilteredRelation class fails to properly sanitize column aliases containing control characters when used with QuerySet methods annotate(), aggregate(), extra(), values(), values_list(), and alias() via dictionary expansion (**kwargs).

Affected versions of the Django package are vulnerable to SQL Injection due to improper sanitization of band index parameters in PostGIS raster lookups. The raster lookup functionality in Django's GIS module fails to properly validate or escape untrusted data used as a band index when performing spatial queries against PostGIS databases.

Affected versions of Django are vulnerable to potential denial-of-service in intcomma template filter when used with very long strings.

A potential denial-of-service vulnerability has been identified in Django's urlize() and urlizetrunc() functions in django.utils.html. This vulnerability can be triggered by inputting huge strings containing a specific sequence of characters.

Django 3.2.14 and 4.0.6 include a fix for CVE-2022-34265: Potential SQL injection via Trunc(kind) and Extract(lookup_name) arguments.
https://www.djangoproject.com/weblog/2022/jul/04/security-releases

An issue was discovered in Django 2.2 before 2.2.13 and 3.0 before 3.0.7. In cases where a memcached backend does not perform key validation, passing malformed cache keys could result in a key collision, and potential data leakage.

Django 4.1.7, 4.0.10 and 3.2.18 include a fix for CVE-2023-24580: Potential denial-of-service vulnerability in file uploads.
https://www.djangoproject.com/weblog/2023/feb/14/security-releases

An issue was discovered in Django 2.2 before 2.2.16, 3.0 before 3.0.10, and 3.1 before 3.1.1 (when Python 3.7+ is used). The intermediate-level directories of the filesystem cache had the system's standard umask rather than 0o077.

Django versions 3.2.2, 3.1.10 and 2.2.22 include a fix for CVE-2021-32052: In Django 2.2 before 2.2.22, 3.1 before 3.1.10, and 3.2 before 3.2.2 (with Python 3.9.5+), URLValidator does not prohibit newlines and tabs (unless the URLField form field is used). If an application uses values with newlines in an HTTP response, header injection can occur. Django itself is unaffected because HttpResponse prohibits newlines in HTTP headers.
https://www.djangoproject.com/weblog/2021/may/06/security-releases

Affected versions of the Django package are vulnerable to Path Traversal due to improper validation of file paths in the django.contrib.admindocs module. The `TemplateDetailView` view allows staff members to verify the existence of arbitrary files by manipulating the file path. An attacker with staff privileges can exploit this vulnerability to check for the presence of files outside the template root directories, and if the `admindocs` templates are customized to display file contents, they can also access the contents of these files.

Django addresses a memory exhaustion issue in django.utils.numberformat.floatformat(). When floatformat receives a string representation of a number in scientific notation with a large exponent, it could lead to excessive memory consumption. To prevent this, decimals with more than 200 digits are now returned as-is.

Django 2.2.24, 3.1.12, and 3.2.4 include a fix for CVE-2021-33571: In Django 2.2 before 2.2.24, 3.x before 3.1.12, and 3.2 before 3.2.4, URLValidator, validate_ipv4_address, and validate_ipv46_address do not prohibit leading zero characters in octal literals. This may allow a bypass of access control that is based on IP addresses. (validate_ipv4_address and validate_ipv46_address are unaffected with Python 3.9.5+).
https://www.djangoproject.com/weblog/2021/jun/02/security-releases

Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to inefficient string concatenation when processing duplicate HTTP headers in ASGI mode. The ASGIRequest class combines repeated headers using repeated string concatenation, resulting in super-linear (quadratic) time complexity when processing requests with many duplicate headers.

Affected versions of the Django package are vulnerable to SQL Injection due to improper handling of column aliases containing periods in QuerySet.order_by() when combined with FilteredRelation. The QuerySet.order_by() method fails to properly sanitize column aliases that contain periods when the same alias is used in FilteredRelation via dictionary expansion. 
https://github.com/django/django/commit/90f5b10784ba5bf369caed87640e2b4394ea3314

Django 2.2.21, 3.1.9 and 3.2.1 include a fix for CVE-2021-31542: MultiPartParser, UploadedFile, and FieldFile allowed directory traversal via uploaded files with suitably crafted file names.
https://www.djangoproject.com/weblog/2021/may/04/security-releases

An issue was discovered in Django 4.2 before 4.2.21, 5.1 before 5.1.9, and 5.2 before 5.2.1. The django.utils.html.strip_tags() function is vulnerable to a potential denial-of-service (slow performance) when processing inputs containing large sequences of incomplete HTML tags. The template filter striptags is also vulnerable, because it is built on top of strip_tags().

In Django 3.2 before 3.2.16, 4.0 before 4.0.8, and 4.1 before 4.1.2, internationalized URLs were subject to a potential denial of service attack via the locale parameter, which is treated as a regular expression.

Affected versions of Django are vulnerable to potential Denial of Service via certain inputs with a very large number of Unicode characters in django.utils.encoding.uri_to_iri().

Django 1.11.29, 2.2.11 and 3.0.4 includes a fix for CVE-2020-9402: Django 1.11 before 1.11.29, 2.2 before 2.2.11, and 3.0 before 3.0.4 allows SQL Injection if untrusted data is used as a tolerance parameter in GIS functions and aggregates on Oracle. By passing a suitably crafted tolerance to GIS functions and aggregates on Oracle, it was possible to break escaping and inject malicious SQL.
https://www.djangoproject.com/weblog/2020/mar/04/security-releases

Django affected versions are vulnerable to a potential SQL injection in the HasKey(lhs, rhs) lookup on Oracle databases. The vulnerability arises when untrusted data is directly used as the lhs value in the django.db.models.fields.json.HasKey lookup. However, applications using the jsonfield.has_key lookup with the __ syntax remain unaffected by this issue.

Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to quadratic time complexity during HTML parsing in text truncation methods. The django.utils.text.Truncator.chars() and Truncator.words() methods (with html=True), as well as the truncatechars_html and truncatewords_html template filters, exhibit quadratic time complexity when processing inputs containing a large number of unmatched HTML end tags.

Django versions 2.2.25, 3.1.14 and 3.2.10 include a fix for CVE-2021-44420: In Django 2.2 before 2.2.25, 3.1 before 3.1.14, and 3.2 before 3.2.10, HTTP requests for URLs with trailing newlines could bypass upstream access control based on URL paths.
https://www.djangoproject.com/weblog/2021/dec/07/security-releases/

Django 2.1.15 and 2.2.8 includes a fix for CVE-2019-19118: A Django model admin displaying inline related models, where the user has view-only permissions to a parent model but edit permissions to the inline model, would be presented with an editing UI, allowing POST requests, for updating the inline model. Directly editing the view-only parent model was not possible, but the parent model's save() method was called, triggering potential side effects, and causing pre and post-save signal handlers to be invoked. To resolve this, the Django admin is adjusted to require edit permissions on the parent model in order for inline models to be editable.

Django 1.11.27, 2.2.9 and 3.0.1 include a fix for CVE-2019-19844: Account takeover. A suitably crafted email address (that is equal to an existing user's email address after case transformation of Unicode characters) would allow an attacker to be sent a password reset token for the matched user account. One mitigation in the new releases is to send password reset tokens only to the registered user email address.

Django has a potential denial-of-service vulnerability in django.utils.html.urlize() and AdminURLFieldWidget. The urlize and urlizetrunc functions, along with AdminURLFieldWidget, are vulnerable to denial-of-service attacks when handling inputs with a very large number of Unicode characters.

Affected versions of Django are potentially vulnerable to denial-of-service via the get_supported_language_variant() method. This method was susceptible to a denial-of-service attack when used with very long strings containing specific characters. Exploiting this vulnerability could cause significant delays or crashes in the affected application, potentially leading to service disruption.

Django versions 2.2.19, 3.0.13 and 3.1.7 include a fix for CVE-2021-23336: Web cache poisoning via 'django.utils.http.limited_parse_qsl()'. Django contains a copy of 'urllib.parse.parse_qsl' which was added to backport some security fixes. A further security fix has been issued recently such that 'parse_qsl(' no longer allows using ';' as a query parameter separator by default.

Django 4.2.1, 4.1.9 and 3.2.19 include a fix for CVE-2023-31047: In Django 3.2 before 3.2.19, 4.x before 4.1.9, and 4.2 before 4.2.1, it was possible to bypass validation when using one form field to upload multiple files. This multiple upload has never been supported by forms.FileField or forms.ImageField (only the last uploaded file was validated). However, Django's "Uploading multiple files" documentation suggested otherwise.
https://www.djangoproject.com/weblog/2023/may/03/security-releases

Affected versions of Django are vulnerable to potential regular expression denial-of-service (REDoS). django.utils.text.Truncator.words() method (with html=True) and truncatewords_html template filter were subject to a potential regular expression denial-of-service attack using a suitably crafted string (follow up to CVE-2019-14232 and CVE-2023-43665).

Affected versions of Django are vulnerable to a potential ReDoS (regular expression denial of service) in EmailValidator and URLValidator via a very large number of domain name labels of emails and URLs.

Django 2.2.27, 3.2.12 and 4.0.2 include a fix for CVE-2022-23833: Denial-of-service possibility in file uploads.
https://www.djangoproject.com/weblog/2022/feb/01/security-releases

Django 2.2.28, 3.2.13 and 4.0.4 include a fix for CVE-2022-28346: An issue was discovered in Django 2.2 before 2.2.28, 3.2 before 3.2.13, and 4.0 before 4.0.4. QuerySet.annotate(), aggregate(), and extra() methods are subject to SQL injection in column aliases via a crafted dictionary (with dictionary expansion) as the passed **kwargs.
https://www.djangoproject.com/weblog/2022/apr/11/security-releases

In Django 2.2 before 2.2.20, 3.0 before 3.0.14, and 3.1 before 3.1.8, MultiPartParser allowed directory traversal via uploaded files with suitably crafted file names. Built-in upload handlers were not affected by this vulnerability.

CVE-2025-64458: Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to slow Unicode NFKC normalization on Windows being applied to untrusted inputs. The django.contrib.auth.views.LoginView and django.contrib.auth.views.LogoutView, and django.views.i18n.set_language normalize user-controlled strings using Python’s NFKC algorithm, which is unusually slow on Windows for huge Unicode sequences and can be triggered to consume excessive CPU.

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45452: Storage.save in Django 2.2 before 2.2.26, 3.2 before 3.2.11, and 4.0 before 4.0.1 allows directory traversal if crafted filenames are directly passed to it.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases/

Affected versions of Django are vulnerable to a potential denial-of-service (DoS) attack in the `django.utils.html.strip_tags()` method. The vulnerability occurs when the `strip_tags()` method or the `striptags` template filter processes inputs containing large sequences of nested, incomplete HTML entities.

Affected versions of the Django package are vulnerable to Information Disclosure (Timing Attack) due to non-constant-time comparison in the mod_wsgi authentication handler. The django.contrib.auth.handlers.modwsgi.check_password() function does not perform user existence checks in constant time, allowing response timing differences to reveal whether usernames exist.

The {% debug %} template tag in Django 2.2 before 2.2.27, 3.2 before 3.2.12, and 4.0 before 4.0.2 does not properly encode the current context. This may lead to XSS.

Django fixes a potential denial-of-service vulnerability in XML ``Deserializer``.

An issue was discovered in Django 5.2 before 5.2.3, 5.1 before 5.1.11, and 4.2 before 4.2.23. Internal HTTP response logging does not escape request.path, which allows remote attackers to potentially manipulate log output via crafted URLs. This may lead to log injection or forgery when logs are viewed in terminals or processed by external systems.

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45116: An issue was discovered in Django 2.2 before 2.2.26, 3.2 before 3.2.11, and 4.0 before 4.0.1. Due to leveraging the Django Template Language's variable resolution logic, the dictsort template filter was potentially vulnerable to information disclosure, or an unintended method call, if passed a suitably crafted key.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45115: UserAttributeSimilarityValidator incurred significant overhead in evaluating a submitted password that was artificially large in relation to the comparison values. In a situation where access to user registration was unrestricted, this provided a potential vector for a denial-of-service attack.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases/

Affected versions of Django are affected by a potential denial-of-service vulnerability in the django.utils.html.urlize() function. The urlize and urlizetrunc template filters were susceptible to a denial-of-service attack via certain inputs containing many brackets. An attacker could exploit this vulnerability to cause significant delays or crashes in the affected application.

Affected versions of Django are affected by a directory-traversal vulnerability in the Storage.save() method. Derived classes of the django.core.files.storage.Storage base class that overrides the generate_filename() method without replicating the file path validations existing in the parent class could allow for directory traversal via certain inputs when calling save(). This could enable an attacker to manipulate file paths and access unintended directories.

Django 1.11.28, 2.2.10 and 3.0.3 include a fix for CVE-2020-7471: SQL Injection if untrusted data is used as a StringAgg delimiter (e.g., in Django applications that offer downloads of data as a series of rows with a user-specified column delimiter). By passing a suitably crafted delimiter to a contrib.postgres.aggregates.StringAgg instance, it was possible to break escaping and inject malicious SQL.

Affected versions of Django has a potential SQL injection vulnerability in the QuerySet.values() and QuerySet.values_list() methods. When used on models with a JSONField, these methods are susceptible to SQL injection through column aliases if a crafted JSON object key is passed as an argument.

A security vulnerability has been discovered in certain versions of Django, affecting the password reset functionality. The PasswordResetForm class in django.contrib.auth.forms inadvertently allowed attackers to enumerate user email addresses by exploiting unhandled exceptions during the email sending process. This could be done by issuing password reset requests and observing the responses. Django has implemented a fix where these exceptions are now caught and logged using the django.contrib.auth logger, preventing potential information leakage through error responses.

Django 2.2.18, 3.0.12 and 3.1.6 include a fix for CVE-2021-3281: The django.utils.archive.extract method (used by "startapp --template" and "startproject --template") allows directory traversal via an archive with absolute paths or relative paths with dot segments.

Django 4.2.7, 4.1.13 and 3.2.23 include a fix for CVE-2023-46695: Potential denial of service vulnerability in UsernameField on Windows.
https://www.djangoproject.com/weblog/2023/nov/01/security-releases

Affected versions of Django are vulnerable to Denial-of-Service via django.utils.text.Truncator. The django.utils.text.Truncator chars() and words() methods (when used with html=True) are subject to a potential DoS (denial of service) attack via certain inputs with very long, potentially malformed HTML text. The chars() and words() methods are used to implement the truncatechars_html and truncatewords_html template filters, which are thus also vulnerable. NOTE: this issue exists because of an incomplete fix for CVE-2019-14232.

Affected versions of Django are affected by a username enumeration vulnerability caused by timing differences in the django.contrib.auth.backends.ModelBackend.authenticate() method. This method allowed remote attackers to enumerate users through a timing attack involving login requests for users with unusable passwords. The timing difference in the authentication process exposed whether a username was valid or not, potentially aiding attackers in gaining unauthorized access.

Django 2.2.28, 3.2.13 and 4.0.4 include a fix for CVE-2022-28347: A SQL injection issue was discovered in QuerySet.explain() in Django 2.2 before 2.2.28, 3.2 before 3.2.13, and 4.0 before 4.0.4. This occurs by passing a crafted dictionary (with dictionary expansion) as the **options argument, and placing the injection payload in an option name.
https://www.djangoproject.com/weblog/2022/apr/11/security-releases

Django 2.2.16, 3.0.10 and 3.1.1 include a fix for CVE-2020-24583: An issue was discovered in Django 2.2 before 2.2.16, 3.0 before 3.0.10, and 3.1 before 3.1.1 (when Python 3.7+ is used). FILE_UPLOAD_DIRECTORY_PERMISSIONS mode was not applied to intermediate-level directories created in the process of uploading files. It was also not applied to intermediate-level collected static directories when using the collectstatic management command.
#NOTE: This vulnerability affects only users of Python versions above 3.7.
https://www.djangoproject.com/weblog/2020/sep/01/security-releases

Django 3.2.17, 4.0.9 and 4.1.6 includes a fix for CVE-2023-23969: In Django 3.2 before 3.2.17, 4.0 before 4.0.9, and 4.1 before 4.1.6, the parsed values of Accept-Language headers are cached in order to avoid repetitive parsing. This leads to a potential denial-of-service vector via excessive memory usage if the raw value of Accept-Language headers is very large.
https://www.djangoproject.com/weblog/2023/feb/01/security-releases

Affected versions of the `django` package are vulnerable to Download of Code Without Integrity Check due to improper handling of user-supplied input in the HTTP FileResponse class. The vulnerability arises because the Content-Disposition header of a FileResponse can be set using a filename derived from user input without sufficient validation. An attacker can exploit this by crafting a request that causes a file with malicious content to be downloaded, potentially executing arbitrary code on the client system when the file is opened.

CVE-2025-64459: Affected versions of the Django package are vulnerable to SQL Injection due to improper input validation, allowing the internal _connector keyword argument to be accepted from untrusted dictionaries via expansion. The .filter(), .exclude(), and .get() methods on QuerySet, as well as the Q class, resolve **kwargs and will treat a supplied _connector value as the logical connector without constraining it to the expected set (AND/OR), permitting attacker-controlled tokens to influence SQL predicate construction.

Affected versions of the Django package are vulnerable to SQL Injection due to insufficient input sanitization in FilteredRelation column aliases. The FilteredRelation class fails to properly validate or escape column alias names when they are provided through dictionary expansion as keyword arguments to QuerySet.annotate() or QuerySet.alias() methods, allowing malicious SQL code to be injected directly into the generated database queries.

Django fixes potential SQL injection in ``FilteredRelation`` column aliases on PostgreSQL.

Affected versions of the sqlparse package are vulnerable to Denial of Service (DoS) due to missing hard limits on token grouping recursion depth and token processing when formatting very large SQL tuple lists. During sqlparse.format() processing, the sqlparse.engine.grouping._group_matching() and sqlparse.engine.grouping._group() functions can recurse and iterate over excessively large tlist.tokens without enforcing MAX_GROUPING_DEPTH or MAX_GROUPING_TOKENS, allowing grouping work to grow until it effectively hangs.

Affected versions of this package are vulnerable to Denial of Service (DoS) attacks due to Algorithmic Complexity. The SQL parser fails to enforce limits when processing deeply nested tuples and large token sequences, leading to excessive resource consumption through crafted SQL statements with extreme nesting depth or token counts.

**Note:** This issue is due to an incomplete fix for CVE-2024-4340.

Sqlparse 0.5.0 addresses a potential denial of service (DoS) vulnerability related to recursion errors in deeply nested SQL statements. To mitigate this issue, the update replaces recursion errors with a general SQLParseError, improving the resilience and stability of the parsing process.

Sqlparse 0.4.4 includes a fix for CVE-2023-30608: Parser contains a regular expression that is vulnerable to ReDOS (Regular Expression Denial of Service).
https://github.com/andialbrecht/sqlparse/security/advisories/GHSA-rrm6-wvj7-cwh2

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to redirect handling that drains connections by decompressing redirect response bodies without enforcing streaming read limits. The issue occurs when using urllib3’s streaming mode (for example, preload_content=False) while allowing redirects, because urllib3.response.HTTPResponse.drain_conn() would call HTTPResponse.read() in a way that decoded/decompressed the entire redirect response body even before any streaming reads were performed, effectively bypassing decompression-bomb safeguards.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to improper handling of highly compressed HTTP response bodies during streaming decompression. The urllib3.HTTPResponse methods stream(), read(), read1(), read_chunked(), and readinto() may fully decompress a minimal but highly compressed payload based on the Content-Encoding header into an internal buffer instead of limiting the decompressed output to the requested chunk size, causing excessive CPU usage and massive memory allocation on the client side.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to allowing an unbounded number of content-encoding decompression steps for HTTP responses. The HTTPResponse content decoding pipeline in urllib3 follows the Content-Encoding header and applies each advertised compression algorithm in sequence without enforcing a maximum chain length or effective output size, so a malicious peer can send a response with a very long encoding chain that triggers excessive CPU use and massive memory allocation during decompression.

Urllib3's ProxyManager ensures that the Proxy-Authorization header is correctly directed only to configured proxies. However, when HTTP requests bypass urllib3's proxy support, there's a risk of inadvertently setting the Proxy-Authorization header, which remains ineffective without a forwarding or tunneling proxy. Urllib3 does not recognize this header as carrying authentication data, failing to remove it during cross-origin redirects. While this scenario is uncommon and poses low risk to most users, urllib3 now proactively removes the Proxy-Authorization header during cross-origin redirects as a precautionary measure. Users are advised to utilize urllib3's proxy support or disable automatic redirects to handle the Proxy-Authorization header securely. Despite these precautions, urllib3 defaults to stripping the header to safeguard users who may inadvertently misconfigure requests.

Urllib3 1.26.17 and 2.0.5 include a fix for CVE-2023-43804: Urllib3 doesn't treat the 'Cookie' HTTP header special or provide any helpers for managing cookies over HTTP, that is the responsibility of the user. However, it is possible for a user to specify a 'Cookie' header and unknowingly leak information via HTTP redirects to a different origin if that user doesn't disable redirects explicitly.
https://github.com/urllib3/urllib3/security/advisories/GHSA-v845-jxx5-vc9f

Urllib3 1.26.5 includes a fix for CVE-2021-33503: When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking, causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redirect.
https://github.com/advisories/GHSA-q2q7-5pp4-w6pg

The _encode_invalid_chars function in util/url.py in the urllib3 library 1.25.2 through 1.25.7 for Python allows a denial of service (CPU consumption) because of an inefficient algorithm. The percent_encodings array contains all matches of percent encodings. It is not deduplicated. For a URL of length N, the size of percent_encodings may be up to O(N). The next step (normalize existing percent-encoded bytes) also takes up to O(N) for each step, so the total time is O(N^2). If percent_encodings were deduplicated, the time to compute _encode_invalid_chars would be O(kN), where k is at most 484 ((10+6*2)^2). See: CVE-2020-7212.

Affected versions of urllib3 are vulnerable to an HTTP redirect handling vulnerability that fails to remove the HTTP request body when a POST changes to a GET via 301, 302, or 303 responses. This flaw can expose sensitive request data if the origin service is compromised and redirects to a malicious endpoint, though exploitability is low when no sensitive data is used. The vulnerability affects automatic redirect behavior. It is fixed in versions 1.26.18 and 2.0.7; update or disable redirects using redirects=False.
This vulnerability is specific to Python's urllib3 library.

urllib3 is a user-friendly HTTP client library for Python. Prior to 2.5.0, it is possible to disable redirects for all requests by instantiating a PoolManager and specifying retries in a way that disable redirects. By default, requests and botocore users are not affected. An application attempting to mitigate SSRF or open redirect vulnerabilities by disabling redirects at the PoolManager level will remain vulnerable. This issue has been patched in version 2.5.0.

Urllib3 1.25.9 includes a fix for CVE-2020-26137: Urllib3 before 1.25.9 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserting CR and LF control characters in the first argument of putrequest(). NOTE: this is similar to CVE-2020-26116.
https://github.com/python/cpython/issues/83784
https://github.com/urllib3/urllib3/pull/1800

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to redirect handling that drains connections by decompressing redirect response bodies without enforcing streaming read limits. The issue occurs when using urllib3’s streaming mode (for example, preload_content=False) while allowing redirects, because urllib3.response.HTTPResponse.drain_conn() would call HTTPResponse.read() in a way that decoded/decompressed the entire redirect response body even before any streaming reads were performed, effectively bypassing decompression-bomb safeguards.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to improper handling of highly compressed HTTP response bodies during streaming decompression. The urllib3.HTTPResponse methods stream(), read(), read1(), read_chunked(), and readinto() may fully decompress a minimal but highly compressed payload based on the Content-Encoding header into an internal buffer instead of limiting the decompressed output to the requested chunk size, causing excessive CPU usage and massive memory allocation on the client side.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to allowing an unbounded number of content-encoding decompression steps for HTTP responses. The HTTPResponse content decoding pipeline in urllib3 follows the Content-Encoding header and applies each advertised compression algorithm in sequence without enforcing a maximum chain length or effective output size, so a malicious peer can send a response with a very long encoding chain that triggers excessive CPU use and massive memory allocation during decompression.

Urllib3's ProxyManager ensures that the Proxy-Authorization header is correctly directed only to configured proxies. However, when HTTP requests bypass urllib3's proxy support, there's a risk of inadvertently setting the Proxy-Authorization header, which remains ineffective without a forwarding or tunneling proxy. Urllib3 does not recognize this header as carrying authentication data, failing to remove it during cross-origin redirects. While this scenario is uncommon and poses low risk to most users, urllib3 now proactively removes the Proxy-Authorization header during cross-origin redirects as a precautionary measure. Users are advised to utilize urllib3's proxy support or disable automatic redirects to handle the Proxy-Authorization header securely. Despite these precautions, urllib3 defaults to stripping the header to safeguard users who may inadvertently misconfigure requests.

Urllib3 1.26.17 and 2.0.5 include a fix for CVE-2023-43804: Urllib3 doesn't treat the 'Cookie' HTTP header special or provide any helpers for managing cookies over HTTP, that is the responsibility of the user. However, it is possible for a user to specify a 'Cookie' header and unknowingly leak information via HTTP redirects to a different origin if that user doesn't disable redirects explicitly.
https://github.com/urllib3/urllib3/security/advisories/GHSA-v845-jxx5-vc9f

Urllib3 1.26.5 includes a fix for CVE-2021-33503: When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking, causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redirect.
https://github.com/advisories/GHSA-q2q7-5pp4-w6pg

The _encode_invalid_chars function in util/url.py in the urllib3 library 1.25.2 through 1.25.7 for Python allows a denial of service (CPU consumption) because of an inefficient algorithm. The percent_encodings array contains all matches of percent encodings. It is not deduplicated. For a URL of length N, the size of percent_encodings may be up to O(N). The next step (normalize existing percent-encoded bytes) also takes up to O(N) for each step, so the total time is O(N^2). If percent_encodings were deduplicated, the time to compute _encode_invalid_chars would be O(kN), where k is at most 484 ((10+6*2)^2). See: CVE-2020-7212.

Affected versions of urllib3 are vulnerable to an HTTP redirect handling vulnerability that fails to remove the HTTP request body when a POST changes to a GET via 301, 302, or 303 responses. This flaw can expose sensitive request data if the origin service is compromised and redirects to a malicious endpoint, though exploitability is low when no sensitive data is used. The vulnerability affects automatic redirect behavior. It is fixed in versions 1.26.18 and 2.0.7; update or disable redirects using redirects=False.
This vulnerability is specific to Python's urllib3 library.

urllib3 is a user-friendly HTTP client library for Python. Prior to 2.5.0, it is possible to disable redirects for all requests by instantiating a PoolManager and specifying retries in a way that disable redirects. By default, requests and botocore users are not affected. An application attempting to mitigate SSRF or open redirect vulnerabilities by disabling redirects at the PoolManager level will remain vulnerable. This issue has been patched in version 2.5.0.

Urllib3 1.25.9 includes a fix for CVE-2020-26137: Urllib3 before 1.25.9 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserting CR and LF control characters in the first argument of putrequest(). NOTE: this is similar to CVE-2020-26116.
https://github.com/python/cpython/issues/83784
https://github.com/urllib3/urllib3/pull/1800

Affected versions of the gunicorn package are vulnerable to HTTP Request/Response Smuggling due to improper validation of the Transfer-Encoding header that enables a TE.CL desynchronisation condition. Gunicorn’s HTTP parser does not consistently enforce RFC semantics when parsing conflicting or unsupported request framing—such as messages containing both Transfer-Encoding and Content-Length—so the backend may fall back to Content-Length while an intermediary treats the message as chunked.

Gunicorn 20.0.1 fixes chunked encoding support to prevent http request smuggling attacks.
https://github.com/benoitc/gunicorn/issues/2176
https://github.com/p4k03n4t0r/http-request-smuggling#request-smuggling-using-mitmproxy-and-gunicorn

Gunicorn fails to properly validate Transfer-Encoding headers, leading to HTTP Request Smuggling (HRS) vulnerabilities. By crafting requests with conflicting Transfer-Encoding headers, attackers can bypass security restrictions and access restricted endpoints. This issue is due to Gunicorn's handling of Transfer-Encoding headers, where it incorrectly processes requests with multiple, conflicting Transfer-Encoding headers, treating them as chunked regardless of the final encoding specified. This vulnerability allows for a range of attacks including cache poisoning, session manipulation, and data exposure.

Requests is an HTTP library. Due to a URL parsing issue, Requests releases prior to 2.32.4 may leak .netrc credentials to third parties for specific maliciously-crafted URLs. Users should upgrade to version 2.32.4 to receive a fix. For older versions of Requests, use of the .netrc file can be disabled with `trust_env=False` on one's Requests Session.

Affected versions of Requests are vulnerable to proxy credential leakage. When redirected to an HTTPS endpoint, the Proxy-Authorization header is forwarded to the destination server due to the use of rebuild_proxies to reattach the header. This may allow a malicious actor to exfiltrate sensitive information.

Affected versions of the requests package are vulnerable to Insecure Temporary File reuse due to predictable temporary filename generation in extract_zipped_paths(). The requests.utils.extract_zipped_paths() utility extracts files from zip archives into the system temporary directory using a deterministic path, and if that file already exists, the function reuses it without validating that it is the expected extracted content.

Affected versions of Requests, when making requests through a Requests `Session`, if the first request is made with `verify=False` to disable cert verification, all subsequent requests to the same host will continue to ignore cert verification regardless of changes to the value of `verify`. This behavior will continue for the lifecycle of the connection in the connection pool. Requests 2.32.0 fixes the issue, but versions 2.32.0 and 2.32.1 were yanked due to conflicts with CVE-2024-35195 mitigation.

Certifi 2022.12.07 includes a fix for CVE-2022-23491: Certifi 2022.12.07 removes root certificates from "TrustCor" from the root store. These are in the process of being removed from Mozilla's trust store. TrustCor's root certificates are being removed pursuant to an investigation prompted by media reporting that TrustCor's ownership also operated a business that produced spyware. Conclusions of Mozilla's investigation can be found in the linked google group discussion.

Certifi 2023.07.22 includes a fix for CVE-2023-37920: Certifi prior to version 2023.07.22 recognizes "e-Tugra" root certificates. e-Tugra's root certificates were subject to an investigation prompted by reporting of security issues in their systems. Certifi 2023.07.22 removes root certificates from "e-Tugra" from the root store.
https://github.com/certifi/python-certifi/security/advisories/GHSA-xqr8-7jwr-rhp7

Certifi 2022.12.07 includes a fix for CVE-2022-23491: Certifi 2022.12.07 removes root certificates from "TrustCor" from the root store. These are in the process of being removed from Mozilla's trust store. TrustCor's root certificates are being removed pursuant to an investigation prompted by media reporting that TrustCor's ownership also operated a business that produced spyware. Conclusions of Mozilla's investigation can be found in the linked google group discussion.

Certifi 2023.07.22 includes a fix for CVE-2023-37920: Certifi prior to version 2023.07.22 recognizes "e-Tugra" root certificates. e-Tugra's root certificates were subject to an investigation prompted by reporting of security issues in their systems. Certifi 2023.07.22 removes root certificates from "e-Tugra" from the root store.
https://github.com/certifi/python-certifi/security/advisories/GHSA-xqr8-7jwr-rhp7

A SQL Injection issue in the SQL Panel in Jazzband Django Debug Toolbar before 1.11.1, 2.x before 2.2.1, and 3.x before 3.2.1 allows attackers to execute SQL statements by changing the raw_sql input field of the SQL explain, analyze, or select form. See CVE-2021-30459.

** DISPUTED ** Py throughout 1.11.0 allows remote attackers to conduct a ReDoS (Regular expression Denial of Service) attack via a Subversion repository with crafted info data because the InfoSvnCommand argument is mishandled.
https://github.com/pytest-dev/py/issues/287

Py 1.10.0 includes a fix for CVE-2020-29651: A denial of service via regular expression in the py.path.svnwc component of py (aka python-py) through 1.9.0 could be used by attackers to cause a compute-time denial of service attack by supplying malicious input to the blame functionality.

Affected versions of Idna are vulnerable to Denial Of Service via the idna.encode(), where a specially crafted argument could lead to significant resource consumption. In version 3.7, this function has been updated to reject such inputs efficiently, minimizing resource use. A practical workaround involves enforcing a maximum domain name length of 253 characters before encoding, as the vulnerability is triggered by unusually large inputs that normal operations wouldn't encounter.

** DISPUTED ** Py throughout 1.11.0 allows remote attackers to conduct a ReDoS (Regular expression Denial of Service) attack via a Subversion repository with crafted info data because the InfoSvnCommand argument is mishandled.
https://github.com/pytest-dev/py/issues/287

Py 1.10.0 includes a fix for CVE-2020-29651: A denial of service via regular expression in the py.path.svnwc component of py (aka python-py) through 1.9.0 could be used by attackers to cause a compute-time denial of service attack by supplying malicious input to the blame functionality.

An issue was discovered in Django 2.2 before 2.2.13 and 3.0 before 3.0.7. Query parameters generated by the Django admin ForeignKeyRawIdWidget were not properly URL encoded, leading to a possibility of an XSS attack.

Affected versions of the Django package are vulnerable to SQL Injection due to improper handling of control characters in column aliases within FilteredRelation. The FilteredRelation class fails to properly sanitize column aliases containing control characters when used with QuerySet methods annotate(), aggregate(), extra(), values(), values_list(), and alias() via dictionary expansion (**kwargs).

Affected versions of the Django package are vulnerable to SQL Injection due to improper sanitization of band index parameters in PostGIS raster lookups. The raster lookup functionality in Django's GIS module fails to properly validate or escape untrusted data used as a band index when performing spatial queries against PostGIS databases.

Affected versions of Django are vulnerable to potential denial-of-service in intcomma template filter when used with very long strings.

A potential denial-of-service vulnerability has been identified in Django's urlize() and urlizetrunc() functions in django.utils.html. This vulnerability can be triggered by inputting huge strings containing a specific sequence of characters.

Django 3.2.14 and 4.0.6 include a fix for CVE-2022-34265: Potential SQL injection via Trunc(kind) and Extract(lookup_name) arguments.
https://www.djangoproject.com/weblog/2022/jul/04/security-releases

An issue was discovered in Django 2.2 before 2.2.13 and 3.0 before 3.0.7. In cases where a memcached backend does not perform key validation, passing malformed cache keys could result in a key collision, and potential data leakage.

Django 4.1.7, 4.0.10 and 3.2.18 include a fix for CVE-2023-24580: Potential denial-of-service vulnerability in file uploads.
https://www.djangoproject.com/weblog/2023/feb/14/security-releases

An issue was discovered in Django 2.2 before 2.2.16, 3.0 before 3.0.10, and 3.1 before 3.1.1 (when Python 3.7+ is used). The intermediate-level directories of the filesystem cache had the system's standard umask rather than 0o077.

Django versions 3.2.2, 3.1.10 and 2.2.22 include a fix for CVE-2021-32052: In Django 2.2 before 2.2.22, 3.1 before 3.1.10, and 3.2 before 3.2.2 (with Python 3.9.5+), URLValidator does not prohibit newlines and tabs (unless the URLField form field is used). If an application uses values with newlines in an HTTP response, header injection can occur. Django itself is unaffected because HttpResponse prohibits newlines in HTTP headers.
https://www.djangoproject.com/weblog/2021/may/06/security-releases

Affected versions of the Django package are vulnerable to Path Traversal due to improper validation of file paths in the django.contrib.admindocs module. The `TemplateDetailView` view allows staff members to verify the existence of arbitrary files by manipulating the file path. An attacker with staff privileges can exploit this vulnerability to check for the presence of files outside the template root directories, and if the `admindocs` templates are customized to display file contents, they can also access the contents of these files.

Django addresses a memory exhaustion issue in django.utils.numberformat.floatformat(). When floatformat receives a string representation of a number in scientific notation with a large exponent, it could lead to excessive memory consumption. To prevent this, decimals with more than 200 digits are now returned as-is.

Django 2.2.24, 3.1.12, and 3.2.4 include a fix for CVE-2021-33571: In Django 2.2 before 2.2.24, 3.x before 3.1.12, and 3.2 before 3.2.4, URLValidator, validate_ipv4_address, and validate_ipv46_address do not prohibit leading zero characters in octal literals. This may allow a bypass of access control that is based on IP addresses. (validate_ipv4_address and validate_ipv46_address are unaffected with Python 3.9.5+).
https://www.djangoproject.com/weblog/2021/jun/02/security-releases

Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to inefficient string concatenation when processing duplicate HTTP headers in ASGI mode. The ASGIRequest class combines repeated headers using repeated string concatenation, resulting in super-linear (quadratic) time complexity when processing requests with many duplicate headers.

Affected versions of the Django package are vulnerable to SQL Injection due to improper handling of column aliases containing periods in QuerySet.order_by() when combined with FilteredRelation. The QuerySet.order_by() method fails to properly sanitize column aliases that contain periods when the same alias is used in FilteredRelation via dictionary expansion. 
https://github.com/django/django/commit/90f5b10784ba5bf369caed87640e2b4394ea3314

Django 2.2.21, 3.1.9 and 3.2.1 include a fix for CVE-2021-31542: MultiPartParser, UploadedFile, and FieldFile allowed directory traversal via uploaded files with suitably crafted file names.
https://www.djangoproject.com/weblog/2021/may/04/security-releases

An issue was discovered in Django 4.2 before 4.2.21, 5.1 before 5.1.9, and 5.2 before 5.2.1. The django.utils.html.strip_tags() function is vulnerable to a potential denial-of-service (slow performance) when processing inputs containing large sequences of incomplete HTML tags. The template filter striptags is also vulnerable, because it is built on top of strip_tags().

In Django 3.2 before 3.2.16, 4.0 before 4.0.8, and 4.1 before 4.1.2, internationalized URLs were subject to a potential denial of service attack via the locale parameter, which is treated as a regular expression.

Affected versions of Django are vulnerable to potential Denial of Service via certain inputs with a very large number of Unicode characters in django.utils.encoding.uri_to_iri().

Django 1.11.29, 2.2.11 and 3.0.4 includes a fix for CVE-2020-9402: Django 1.11 before 1.11.29, 2.2 before 2.2.11, and 3.0 before 3.0.4 allows SQL Injection if untrusted data is used as a tolerance parameter in GIS functions and aggregates on Oracle. By passing a suitably crafted tolerance to GIS functions and aggregates on Oracle, it was possible to break escaping and inject malicious SQL.
https://www.djangoproject.com/weblog/2020/mar/04/security-releases

Django affected versions are vulnerable to a potential SQL injection in the HasKey(lhs, rhs) lookup on Oracle databases. The vulnerability arises when untrusted data is directly used as the lhs value in the django.db.models.fields.json.HasKey lookup. However, applications using the jsonfield.has_key lookup with the __ syntax remain unaffected by this issue.

Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to quadratic time complexity during HTML parsing in text truncation methods. The django.utils.text.Truncator.chars() and Truncator.words() methods (with html=True), as well as the truncatechars_html and truncatewords_html template filters, exhibit quadratic time complexity when processing inputs containing a large number of unmatched HTML end tags.

Django versions 2.2.25, 3.1.14 and 3.2.10 include a fix for CVE-2021-44420: In Django 2.2 before 2.2.25, 3.1 before 3.1.14, and 3.2 before 3.2.10, HTTP requests for URLs with trailing newlines could bypass upstream access control based on URL paths.
https://www.djangoproject.com/weblog/2021/dec/07/security-releases/

Django 2.1.15 and 2.2.8 includes a fix for CVE-2019-19118: A Django model admin displaying inline related models, where the user has view-only permissions to a parent model but edit permissions to the inline model, would be presented with an editing UI, allowing POST requests, for updating the inline model. Directly editing the view-only parent model was not possible, but the parent model's save() method was called, triggering potential side effects, and causing pre and post-save signal handlers to be invoked. To resolve this, the Django admin is adjusted to require edit permissions on the parent model in order for inline models to be editable.

Django 1.11.27, 2.2.9 and 3.0.1 include a fix for CVE-2019-19844: Account takeover. A suitably crafted email address (that is equal to an existing user's email address after case transformation of Unicode characters) would allow an attacker to be sent a password reset token for the matched user account. One mitigation in the new releases is to send password reset tokens only to the registered user email address.

Django has a potential denial-of-service vulnerability in django.utils.html.urlize() and AdminURLFieldWidget. The urlize and urlizetrunc functions, along with AdminURLFieldWidget, are vulnerable to denial-of-service attacks when handling inputs with a very large number of Unicode characters.

Affected versions of Django are potentially vulnerable to denial-of-service via the get_supported_language_variant() method. This method was susceptible to a denial-of-service attack when used with very long strings containing specific characters. Exploiting this vulnerability could cause significant delays or crashes in the affected application, potentially leading to service disruption.

Django versions 2.2.19, 3.0.13 and 3.1.7 include a fix for CVE-2021-23336: Web cache poisoning via 'django.utils.http.limited_parse_qsl()'. Django contains a copy of 'urllib.parse.parse_qsl' which was added to backport some security fixes. A further security fix has been issued recently such that 'parse_qsl(' no longer allows using ';' as a query parameter separator by default.

Django 4.2.1, 4.1.9 and 3.2.19 include a fix for CVE-2023-31047: In Django 3.2 before 3.2.19, 4.x before 4.1.9, and 4.2 before 4.2.1, it was possible to bypass validation when using one form field to upload multiple files. This multiple upload has never been supported by forms.FileField or forms.ImageField (only the last uploaded file was validated). However, Django's "Uploading multiple files" documentation suggested otherwise.
https://www.djangoproject.com/weblog/2023/may/03/security-releases

Affected versions of Django are vulnerable to potential regular expression denial-of-service (REDoS). django.utils.text.Truncator.words() method (with html=True) and truncatewords_html template filter were subject to a potential regular expression denial-of-service attack using a suitably crafted string (follow up to CVE-2019-14232 and CVE-2023-43665).

Affected versions of Django are vulnerable to a potential ReDoS (regular expression denial of service) in EmailValidator and URLValidator via a very large number of domain name labels of emails and URLs.

Django 2.2.27, 3.2.12 and 4.0.2 include a fix for CVE-2022-23833: Denial-of-service possibility in file uploads.
https://www.djangoproject.com/weblog/2022/feb/01/security-releases

Django 2.2.28, 3.2.13 and 4.0.4 include a fix for CVE-2022-28346: An issue was discovered in Django 2.2 before 2.2.28, 3.2 before 3.2.13, and 4.0 before 4.0.4. QuerySet.annotate(), aggregate(), and extra() methods are subject to SQL injection in column aliases via a crafted dictionary (with dictionary expansion) as the passed **kwargs.
https://www.djangoproject.com/weblog/2022/apr/11/security-releases

In Django 2.2 before 2.2.20, 3.0 before 3.0.14, and 3.1 before 3.1.8, MultiPartParser allowed directory traversal via uploaded files with suitably crafted file names. Built-in upload handlers were not affected by this vulnerability.

CVE-2025-64458: Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to slow Unicode NFKC normalization on Windows being applied to untrusted inputs. The django.contrib.auth.views.LoginView and django.contrib.auth.views.LogoutView, and django.views.i18n.set_language normalize user-controlled strings using Python’s NFKC algorithm, which is unusually slow on Windows for huge Unicode sequences and can be triggered to consume excessive CPU.

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45452: Storage.save in Django 2.2 before 2.2.26, 3.2 before 3.2.11, and 4.0 before 4.0.1 allows directory traversal if crafted filenames are directly passed to it.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases/

Affected versions of Django are vulnerable to a potential denial-of-service (DoS) attack in the `django.utils.html.strip_tags()` method. The vulnerability occurs when the `strip_tags()` method or the `striptags` template filter processes inputs containing large sequences of nested, incomplete HTML entities.

Affected versions of the Django package are vulnerable to Information Disclosure (Timing Attack) due to non-constant-time comparison in the mod_wsgi authentication handler. The django.contrib.auth.handlers.modwsgi.check_password() function does not perform user existence checks in constant time, allowing response timing differences to reveal whether usernames exist.

The {% debug %} template tag in Django 2.2 before 2.2.27, 3.2 before 3.2.12, and 4.0 before 4.0.2 does not properly encode the current context. This may lead to XSS.

Django fixes a potential denial-of-service vulnerability in XML ``Deserializer``.

An issue was discovered in Django 5.2 before 5.2.3, 5.1 before 5.1.11, and 4.2 before 4.2.23. Internal HTTP response logging does not escape request.path, which allows remote attackers to potentially manipulate log output via crafted URLs. This may lead to log injection or forgery when logs are viewed in terminals or processed by external systems.

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45116: An issue was discovered in Django 2.2 before 2.2.26, 3.2 before 3.2.11, and 4.0 before 4.0.1. Due to leveraging the Django Template Language's variable resolution logic, the dictsort template filter was potentially vulnerable to information disclosure, or an unintended method call, if passed a suitably crafted key.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45115: UserAttributeSimilarityValidator incurred significant overhead in evaluating a submitted password that was artificially large in relation to the comparison values. In a situation where access to user registration was unrestricted, this provided a potential vector for a denial-of-service attack.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases/

Affected versions of Django are affected by a potential denial-of-service vulnerability in the django.utils.html.urlize() function. The urlize and urlizetrunc template filters were susceptible to a denial-of-service attack via certain inputs containing many brackets. An attacker could exploit this vulnerability to cause significant delays or crashes in the affected application.

Affected versions of Django are affected by a directory-traversal vulnerability in the Storage.save() method. Derived classes of the django.core.files.storage.Storage base class that overrides the generate_filename() method without replicating the file path validations existing in the parent class could allow for directory traversal via certain inputs when calling save(). This could enable an attacker to manipulate file paths and access unintended directories.

Django 1.11.28, 2.2.10 and 3.0.3 include a fix for CVE-2020-7471: SQL Injection if untrusted data is used as a StringAgg delimiter (e.g., in Django applications that offer downloads of data as a series of rows with a user-specified column delimiter). By passing a suitably crafted delimiter to a contrib.postgres.aggregates.StringAgg instance, it was possible to break escaping and inject malicious SQL.

Affected versions of Django has a potential SQL injection vulnerability in the QuerySet.values() and QuerySet.values_list() methods. When used on models with a JSONField, these methods are susceptible to SQL injection through column aliases if a crafted JSON object key is passed as an argument.

A security vulnerability has been discovered in certain versions of Django, affecting the password reset functionality. The PasswordResetForm class in django.contrib.auth.forms inadvertently allowed attackers to enumerate user email addresses by exploiting unhandled exceptions during the email sending process. This could be done by issuing password reset requests and observing the responses. Django has implemented a fix where these exceptions are now caught and logged using the django.contrib.auth logger, preventing potential information leakage through error responses.

Django 2.2.18, 3.0.12 and 3.1.6 include a fix for CVE-2021-3281: The django.utils.archive.extract method (used by "startapp --template" and "startproject --template") allows directory traversal via an archive with absolute paths or relative paths with dot segments.

Django 4.2.7, 4.1.13 and 3.2.23 include a fix for CVE-2023-46695: Potential denial of service vulnerability in UsernameField on Windows.
https://www.djangoproject.com/weblog/2023/nov/01/security-releases

Affected versions of Django are vulnerable to Denial-of-Service via django.utils.text.Truncator. The django.utils.text.Truncator chars() and words() methods (when used with html=True) are subject to a potential DoS (denial of service) attack via certain inputs with very long, potentially malformed HTML text. The chars() and words() methods are used to implement the truncatechars_html and truncatewords_html template filters, which are thus also vulnerable. NOTE: this issue exists because of an incomplete fix for CVE-2019-14232.

Affected versions of Django are affected by a username enumeration vulnerability caused by timing differences in the django.contrib.auth.backends.ModelBackend.authenticate() method. This method allowed remote attackers to enumerate users through a timing attack involving login requests for users with unusable passwords. The timing difference in the authentication process exposed whether a username was valid or not, potentially aiding attackers in gaining unauthorized access.

Django 2.2.28, 3.2.13 and 4.0.4 include a fix for CVE-2022-28347: A SQL injection issue was discovered in QuerySet.explain() in Django 2.2 before 2.2.28, 3.2 before 3.2.13, and 4.0 before 4.0.4. This occurs by passing a crafted dictionary (with dictionary expansion) as the **options argument, and placing the injection payload in an option name.
https://www.djangoproject.com/weblog/2022/apr/11/security-releases

Django 2.2.16, 3.0.10 and 3.1.1 include a fix for CVE-2020-24583: An issue was discovered in Django 2.2 before 2.2.16, 3.0 before 3.0.10, and 3.1 before 3.1.1 (when Python 3.7+ is used). FILE_UPLOAD_DIRECTORY_PERMISSIONS mode was not applied to intermediate-level directories created in the process of uploading files. It was also not applied to intermediate-level collected static directories when using the collectstatic management command.
#NOTE: This vulnerability affects only users of Python versions above 3.7.
https://www.djangoproject.com/weblog/2020/sep/01/security-releases

Django 3.2.17, 4.0.9 and 4.1.6 includes a fix for CVE-2023-23969: In Django 3.2 before 3.2.17, 4.0 before 4.0.9, and 4.1 before 4.1.6, the parsed values of Accept-Language headers are cached in order to avoid repetitive parsing. This leads to a potential denial-of-service vector via excessive memory usage if the raw value of Accept-Language headers is very large.
https://www.djangoproject.com/weblog/2023/feb/01/security-releases

Affected versions of the `django` package are vulnerable to Download of Code Without Integrity Check due to improper handling of user-supplied input in the HTTP FileResponse class. The vulnerability arises because the Content-Disposition header of a FileResponse can be set using a filename derived from user input without sufficient validation. An attacker can exploit this by crafting a request that causes a file with malicious content to be downloaded, potentially executing arbitrary code on the client system when the file is opened.

CVE-2025-64459: Affected versions of the Django package are vulnerable to SQL Injection due to improper input validation, allowing the internal _connector keyword argument to be accepted from untrusted dictionaries via expansion. The .filter(), .exclude(), and .get() methods on QuerySet, as well as the Q class, resolve **kwargs and will treat a supplied _connector value as the logical connector without constraining it to the expected set (AND/OR), permitting attacker-controlled tokens to influence SQL predicate construction.

Affected versions of the Django package are vulnerable to SQL Injection due to insufficient input sanitization in FilteredRelation column aliases. The FilteredRelation class fails to properly validate or escape column alias names when they are provided through dictionary expansion as keyword arguments to QuerySet.annotate() or QuerySet.alias() methods, allowing malicious SQL code to be injected directly into the generated database queries.

Django fixes potential SQL injection in ``FilteredRelation`` column aliases on PostgreSQL.

Affected versions of the sqlparse package are vulnerable to Denial of Service (DoS) due to missing hard limits on token grouping recursion depth and token processing when formatting very large SQL tuple lists. During sqlparse.format() processing, the sqlparse.engine.grouping._group_matching() and sqlparse.engine.grouping._group() functions can recurse and iterate over excessively large tlist.tokens without enforcing MAX_GROUPING_DEPTH or MAX_GROUPING_TOKENS, allowing grouping work to grow until it effectively hangs.

Affected versions of this package are vulnerable to Denial of Service (DoS) attacks due to Algorithmic Complexity. The SQL parser fails to enforce limits when processing deeply nested tuples and large token sequences, leading to excessive resource consumption through crafted SQL statements with extreme nesting depth or token counts.

**Note:** This issue is due to an incomplete fix for CVE-2024-4340.

Sqlparse 0.5.0 addresses a potential denial of service (DoS) vulnerability related to recursion errors in deeply nested SQL statements. To mitigate this issue, the update replaces recursion errors with a general SQLParseError, improving the resilience and stability of the parsing process.

Sqlparse 0.4.4 includes a fix for CVE-2023-30608: Parser contains a regular expression that is vulnerable to ReDOS (Regular Expression Denial of Service).
https://github.com/andialbrecht/sqlparse/security/advisories/GHSA-rrm6-wvj7-cwh2

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to redirect handling that drains connections by decompressing redirect response bodies without enforcing streaming read limits. The issue occurs when using urllib3’s streaming mode (for example, preload_content=False) while allowing redirects, because urllib3.response.HTTPResponse.drain_conn() would call HTTPResponse.read() in a way that decoded/decompressed the entire redirect response body even before any streaming reads were performed, effectively bypassing decompression-bomb safeguards.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to improper handling of highly compressed HTTP response bodies during streaming decompression. The urllib3.HTTPResponse methods stream(), read(), read1(), read_chunked(), and readinto() may fully decompress a minimal but highly compressed payload based on the Content-Encoding header into an internal buffer instead of limiting the decompressed output to the requested chunk size, causing excessive CPU usage and massive memory allocation on the client side.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to allowing an unbounded number of content-encoding decompression steps for HTTP responses. The HTTPResponse content decoding pipeline in urllib3 follows the Content-Encoding header and applies each advertised compression algorithm in sequence without enforcing a maximum chain length or effective output size, so a malicious peer can send a response with a very long encoding chain that triggers excessive CPU use and massive memory allocation during decompression.

Urllib3's ProxyManager ensures that the Proxy-Authorization header is correctly directed only to configured proxies. However, when HTTP requests bypass urllib3's proxy support, there's a risk of inadvertently setting the Proxy-Authorization header, which remains ineffective without a forwarding or tunneling proxy. Urllib3 does not recognize this header as carrying authentication data, failing to remove it during cross-origin redirects. While this scenario is uncommon and poses low risk to most users, urllib3 now proactively removes the Proxy-Authorization header during cross-origin redirects as a precautionary measure. Users are advised to utilize urllib3's proxy support or disable automatic redirects to handle the Proxy-Authorization header securely. Despite these precautions, urllib3 defaults to stripping the header to safeguard users who may inadvertently misconfigure requests.

Urllib3 1.26.17 and 2.0.5 include a fix for CVE-2023-43804: Urllib3 doesn't treat the 'Cookie' HTTP header special or provide any helpers for managing cookies over HTTP, that is the responsibility of the user. However, it is possible for a user to specify a 'Cookie' header and unknowingly leak information via HTTP redirects to a different origin if that user doesn't disable redirects explicitly.
https://github.com/urllib3/urllib3/security/advisories/GHSA-v845-jxx5-vc9f

Urllib3 1.26.5 includes a fix for CVE-2021-33503: When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking, causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redirect.
https://github.com/advisories/GHSA-q2q7-5pp4-w6pg

The _encode_invalid_chars function in util/url.py in the urllib3 library 1.25.2 through 1.25.7 for Python allows a denial of service (CPU consumption) because of an inefficient algorithm. The percent_encodings array contains all matches of percent encodings. It is not deduplicated. For a URL of length N, the size of percent_encodings may be up to O(N). The next step (normalize existing percent-encoded bytes) also takes up to O(N) for each step, so the total time is O(N^2). If percent_encodings were deduplicated, the time to compute _encode_invalid_chars would be O(kN), where k is at most 484 ((10+6*2)^2). See: CVE-2020-7212.

Affected versions of urllib3 are vulnerable to an HTTP redirect handling vulnerability that fails to remove the HTTP request body when a POST changes to a GET via 301, 302, or 303 responses. This flaw can expose sensitive request data if the origin service is compromised and redirects to a malicious endpoint, though exploitability is low when no sensitive data is used. The vulnerability affects automatic redirect behavior. It is fixed in versions 1.26.18 and 2.0.7; update or disable redirects using redirects=False.
This vulnerability is specific to Python's urllib3 library.

urllib3 is a user-friendly HTTP client library for Python. Prior to 2.5.0, it is possible to disable redirects for all requests by instantiating a PoolManager and specifying retries in a way that disable redirects. By default, requests and botocore users are not affected. An application attempting to mitigate SSRF or open redirect vulnerabilities by disabling redirects at the PoolManager level will remain vulnerable. This issue has been patched in version 2.5.0.

Urllib3 1.25.9 includes a fix for CVE-2020-26137: Urllib3 before 1.25.9 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserting CR and LF control characters in the first argument of putrequest(). NOTE: this is similar to CVE-2020-26116.
https://github.com/python/cpython/issues/83784
https://github.com/urllib3/urllib3/pull/1800

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to redirect handling that drains connections by decompressing redirect response bodies without enforcing streaming read limits. The issue occurs when using urllib3’s streaming mode (for example, preload_content=False) while allowing redirects, because urllib3.response.HTTPResponse.drain_conn() would call HTTPResponse.read() in a way that decoded/decompressed the entire redirect response body even before any streaming reads were performed, effectively bypassing decompression-bomb safeguards.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to improper handling of highly compressed HTTP response bodies during streaming decompression. The urllib3.HTTPResponse methods stream(), read(), read1(), read_chunked(), and readinto() may fully decompress a minimal but highly compressed payload based on the Content-Encoding header into an internal buffer instead of limiting the decompressed output to the requested chunk size, causing excessive CPU usage and massive memory allocation on the client side.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to allowing an unbounded number of content-encoding decompression steps for HTTP responses. The HTTPResponse content decoding pipeline in urllib3 follows the Content-Encoding header and applies each advertised compression algorithm in sequence without enforcing a maximum chain length or effective output size, so a malicious peer can send a response with a very long encoding chain that triggers excessive CPU use and massive memory allocation during decompression.

Urllib3's ProxyManager ensures that the Proxy-Authorization header is correctly directed only to configured proxies. However, when HTTP requests bypass urllib3's proxy support, there's a risk of inadvertently setting the Proxy-Authorization header, which remains ineffective without a forwarding or tunneling proxy. Urllib3 does not recognize this header as carrying authentication data, failing to remove it during cross-origin redirects. While this scenario is uncommon and poses low risk to most users, urllib3 now proactively removes the Proxy-Authorization header during cross-origin redirects as a precautionary measure. Users are advised to utilize urllib3's proxy support or disable automatic redirects to handle the Proxy-Authorization header securely. Despite these precautions, urllib3 defaults to stripping the header to safeguard users who may inadvertently misconfigure requests.

Urllib3 1.26.17 and 2.0.5 include a fix for CVE-2023-43804: Urllib3 doesn't treat the 'Cookie' HTTP header special or provide any helpers for managing cookies over HTTP, that is the responsibility of the user. However, it is possible for a user to specify a 'Cookie' header and unknowingly leak information via HTTP redirects to a different origin if that user doesn't disable redirects explicitly.
https://github.com/urllib3/urllib3/security/advisories/GHSA-v845-jxx5-vc9f

Urllib3 1.26.5 includes a fix for CVE-2021-33503: When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking, causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redirect.
https://github.com/advisories/GHSA-q2q7-5pp4-w6pg

The _encode_invalid_chars function in util/url.py in the urllib3 library 1.25.2 through 1.25.7 for Python allows a denial of service (CPU consumption) because of an inefficient algorithm. The percent_encodings array contains all matches of percent encodings. It is not deduplicated. For a URL of length N, the size of percent_encodings may be up to O(N). The next step (normalize existing percent-encoded bytes) also takes up to O(N) for each step, so the total time is O(N^2). If percent_encodings were deduplicated, the time to compute _encode_invalid_chars would be O(kN), where k is at most 484 ((10+6*2)^2). See: CVE-2020-7212.

Affected versions of urllib3 are vulnerable to an HTTP redirect handling vulnerability that fails to remove the HTTP request body when a POST changes to a GET via 301, 302, or 303 responses. This flaw can expose sensitive request data if the origin service is compromised and redirects to a malicious endpoint, though exploitability is low when no sensitive data is used. The vulnerability affects automatic redirect behavior. It is fixed in versions 1.26.18 and 2.0.7; update or disable redirects using redirects=False.
This vulnerability is specific to Python's urllib3 library.

urllib3 is a user-friendly HTTP client library for Python. Prior to 2.5.0, it is possible to disable redirects for all requests by instantiating a PoolManager and specifying retries in a way that disable redirects. By default, requests and botocore users are not affected. An application attempting to mitigate SSRF or open redirect vulnerabilities by disabling redirects at the PoolManager level will remain vulnerable. This issue has been patched in version 2.5.0.

Urllib3 1.25.9 includes a fix for CVE-2020-26137: Urllib3 before 1.25.9 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserting CR and LF control characters in the first argument of putrequest(). NOTE: this is similar to CVE-2020-26116.
https://github.com/python/cpython/issues/83784
https://github.com/urllib3/urllib3/pull/1800

Affected versions of the gunicorn package are vulnerable to HTTP Request/Response Smuggling due to improper validation of the Transfer-Encoding header that enables a TE.CL desynchronisation condition. Gunicorn’s HTTP parser does not consistently enforce RFC semantics when parsing conflicting or unsupported request framing—such as messages containing both Transfer-Encoding and Content-Length—so the backend may fall back to Content-Length while an intermediary treats the message as chunked.

Gunicorn 20.0.1 fixes chunked encoding support to prevent http request smuggling attacks.
https://github.com/benoitc/gunicorn/issues/2176
https://github.com/p4k03n4t0r/http-request-smuggling#request-smuggling-using-mitmproxy-and-gunicorn

Gunicorn fails to properly validate Transfer-Encoding headers, leading to HTTP Request Smuggling (HRS) vulnerabilities. By crafting requests with conflicting Transfer-Encoding headers, attackers can bypass security restrictions and access restricted endpoints. This issue is due to Gunicorn's handling of Transfer-Encoding headers, where it incorrectly processes requests with multiple, conflicting Transfer-Encoding headers, treating them as chunked regardless of the final encoding specified. This vulnerability allows for a range of attacks including cache poisoning, session manipulation, and data exposure.

Requests is an HTTP library. Due to a URL parsing issue, Requests releases prior to 2.32.4 may leak .netrc credentials to third parties for specific maliciously-crafted URLs. Users should upgrade to version 2.32.4 to receive a fix. For older versions of Requests, use of the .netrc file can be disabled with `trust_env=False` on one's Requests Session.

Affected versions of Requests are vulnerable to proxy credential leakage. When redirected to an HTTPS endpoint, the Proxy-Authorization header is forwarded to the destination server due to the use of rebuild_proxies to reattach the header. This may allow a malicious actor to exfiltrate sensitive information.

Affected versions of the requests package are vulnerable to Insecure Temporary File reuse due to predictable temporary filename generation in extract_zipped_paths(). The requests.utils.extract_zipped_paths() utility extracts files from zip archives into the system temporary directory using a deterministic path, and if that file already exists, the function reuses it without validating that it is the expected extracted content.

Affected versions of Requests, when making requests through a Requests `Session`, if the first request is made with `verify=False` to disable cert verification, all subsequent requests to the same host will continue to ignore cert verification regardless of changes to the value of `verify`. This behavior will continue for the lifecycle of the connection in the connection pool. Requests 2.32.0 fixes the issue, but versions 2.32.0 and 2.32.1 were yanked due to conflicts with CVE-2024-35195 mitigation.

Certifi 2022.12.07 includes a fix for CVE-2022-23491: Certifi 2022.12.07 removes root certificates from "TrustCor" from the root store. These are in the process of being removed from Mozilla's trust store. TrustCor's root certificates are being removed pursuant to an investigation prompted by media reporting that TrustCor's ownership also operated a business that produced spyware. Conclusions of Mozilla's investigation can be found in the linked google group discussion.

Certifi 2023.07.22 includes a fix for CVE-2023-37920: Certifi prior to version 2023.07.22 recognizes "e-Tugra" root certificates. e-Tugra's root certificates were subject to an investigation prompted by reporting of security issues in their systems. Certifi 2023.07.22 removes root certificates from "e-Tugra" from the root store.
https://github.com/certifi/python-certifi/security/advisories/GHSA-xqr8-7jwr-rhp7

Certifi 2022.12.07 includes a fix for CVE-2022-23491: Certifi 2022.12.07 removes root certificates from "TrustCor" from the root store. These are in the process of being removed from Mozilla's trust store. TrustCor's root certificates are being removed pursuant to an investigation prompted by media reporting that TrustCor's ownership also operated a business that produced spyware. Conclusions of Mozilla's investigation can be found in the linked google group discussion.

Certifi 2023.07.22 includes a fix for CVE-2023-37920: Certifi prior to version 2023.07.22 recognizes "e-Tugra" root certificates. e-Tugra's root certificates were subject to an investigation prompted by reporting of security issues in their systems. Certifi 2023.07.22 removes root certificates from "e-Tugra" from the root store.
https://github.com/certifi/python-certifi/security/advisories/GHSA-xqr8-7jwr-rhp7

Affected versions of Sentry's Python SDK are vulnerable to unintentional exposure of environment variables to subprocesses despite the env={} setting. In Python's 'subprocess' calls, all environment variables are passed to subprocesses by default. However, if you specifically do not want them to be passed to subprocesses, you may use 'env' argument in 'subprocess' calls. Due to the bug in Sentry SDK, with the Stdlib integration enabled (which is enabled by default), this expectation is not fulfilled, and all environment variables are being passed to subprocesses instead. 
As a workaround, and if passing environment variables to child processes poses a security risk for you, you can disable all default integrations.

Sentry-sdk 1.14.0 includes a fix for CVE-2023-28117: When using the Django integration of versions prior to 1.14.0 of the Sentry SDK in a specific configuration it is possible to leak sensitive cookies values, including the session cookie to Sentry. These sensitive cookies could then be used by someone with access to your Sentry issues to impersonate or escalate their privileges within your application. In order for these sensitive values to be leaked, the Sentry SDK configuration must have 'sendDefaultPII' set to 'True'; one must use a custom name for either 'SESSION_COOKIE_NAME' or 'CSRF_COOKIE_NAME' in one's Django settings; and one must not be configured in one's organization or project settings to use Sentry's data scrubbing features to account for the custom cookie names. As of version 1.14.0, the Django integration of the 'sentry-sdk' will detect the custom cookie names based on one's Django settings and will remove the values from the payload before sending the data to Sentry. As a workaround, use the SDK's filtering mechanism to remove the cookies from the payload that is sent to Sentry. For error events, this can be done with the 'before_send' callback method and for performance related events (transactions) one can use the 'before_send_transaction' callback method. Those who want to handle filtering of these values on the server-side can also use Sentry's advanced data scrubbing feature to account for the custom cookie names. Look for the '$http.cookies', '$http.headers', '$request.cookies', or '$request.headers' fields to target with a scrubbing rule.
https://github.com/getsentry/sentry-python/security/advisories/GHSA-29pr-6jr8-q5jm

Sentry-sdk 1.4.1 includes a fix for a Race Condition vulnerability.
https://github.com/getsentry/sentry-python/pull/1203

A SQL Injection issue in the SQL Panel in Jazzband Django Debug Toolbar before 1.11.1, 2.x before 2.2.1, and 3.x before 3.2.1 allows attackers to execute SQL statements by changing the raw_sql input field of the SQL explain, analyze, or select form. See CVE-2021-30459.

** DISPUTED ** Py throughout 1.11.0 allows remote attackers to conduct a ReDoS (Regular expression Denial of Service) attack via a Subversion repository with crafted info data because the InfoSvnCommand argument is mishandled.
https://github.com/pytest-dev/py/issues/287

Py 1.10.0 includes a fix for CVE-2020-29651: A denial of service via regular expression in the py.path.svnwc component of py (aka python-py) through 1.9.0 could be used by attackers to cause a compute-time denial of service attack by supplying malicious input to the blame functionality.

Affected versions of Idna are vulnerable to Denial Of Service via the idna.encode(), where a specially crafted argument could lead to significant resource consumption. In version 3.7, this function has been updated to reject such inputs efficiently, minimizing resource use. A practical workaround involves enforcing a maximum domain name length of 253 characters before encoding, as the vulnerability is triggered by unusually large inputs that normal operations wouldn't encounter.

** DISPUTED ** Py throughout 1.11.0 allows remote attackers to conduct a ReDoS (Regular expression Denial of Service) attack via a Subversion repository with crafted info data because the InfoSvnCommand argument is mishandled.
https://github.com/pytest-dev/py/issues/287

Py 1.10.0 includes a fix for CVE-2020-29651: A denial of service via regular expression in the py.path.svnwc component of py (aka python-py) through 1.9.0 could be used by attackers to cause a compute-time denial of service attack by supplying malicious input to the blame functionality.

An issue was discovered in Django 2.2 before 2.2.13 and 3.0 before 3.0.7. Query parameters generated by the Django admin ForeignKeyRawIdWidget were not properly URL encoded, leading to a possibility of an XSS attack.

Affected versions of the Django package are vulnerable to SQL Injection due to improper handling of control characters in column aliases within FilteredRelation. The FilteredRelation class fails to properly sanitize column aliases containing control characters when used with QuerySet methods annotate(), aggregate(), extra(), values(), values_list(), and alias() via dictionary expansion (**kwargs).

Affected versions of the Django package are vulnerable to SQL Injection due to improper sanitization of band index parameters in PostGIS raster lookups. The raster lookup functionality in Django's GIS module fails to properly validate or escape untrusted data used as a band index when performing spatial queries against PostGIS databases.

Affected versions of Django are vulnerable to potential denial-of-service in intcomma template filter when used with very long strings.

A potential denial-of-service vulnerability has been identified in Django's urlize() and urlizetrunc() functions in django.utils.html. This vulnerability can be triggered by inputting huge strings containing a specific sequence of characters.

Django 3.2.14 and 4.0.6 include a fix for CVE-2022-34265: Potential SQL injection via Trunc(kind) and Extract(lookup_name) arguments.
https://www.djangoproject.com/weblog/2022/jul/04/security-releases

An issue was discovered in Django 2.2 before 2.2.13 and 3.0 before 3.0.7. In cases where a memcached backend does not perform key validation, passing malformed cache keys could result in a key collision, and potential data leakage.

Django 4.1.7, 4.0.10 and 3.2.18 include a fix for CVE-2023-24580: Potential denial-of-service vulnerability in file uploads.
https://www.djangoproject.com/weblog/2023/feb/14/security-releases

An issue was discovered in Django 2.2 before 2.2.16, 3.0 before 3.0.10, and 3.1 before 3.1.1 (when Python 3.7+ is used). The intermediate-level directories of the filesystem cache had the system's standard umask rather than 0o077.

Django versions 3.2.2, 3.1.10 and 2.2.22 include a fix for CVE-2021-32052: In Django 2.2 before 2.2.22, 3.1 before 3.1.10, and 3.2 before 3.2.2 (with Python 3.9.5+), URLValidator does not prohibit newlines and tabs (unless the URLField form field is used). If an application uses values with newlines in an HTTP response, header injection can occur. Django itself is unaffected because HttpResponse prohibits newlines in HTTP headers.
https://www.djangoproject.com/weblog/2021/may/06/security-releases

Affected versions of the Django package are vulnerable to Path Traversal due to improper validation of file paths in the django.contrib.admindocs module. The `TemplateDetailView` view allows staff members to verify the existence of arbitrary files by manipulating the file path. An attacker with staff privileges can exploit this vulnerability to check for the presence of files outside the template root directories, and if the `admindocs` templates are customized to display file contents, they can also access the contents of these files.

Django addresses a memory exhaustion issue in django.utils.numberformat.floatformat(). When floatformat receives a string representation of a number in scientific notation with a large exponent, it could lead to excessive memory consumption. To prevent this, decimals with more than 200 digits are now returned as-is.

Django 2.2.24, 3.1.12, and 3.2.4 include a fix for CVE-2021-33571: In Django 2.2 before 2.2.24, 3.x before 3.1.12, and 3.2 before 3.2.4, URLValidator, validate_ipv4_address, and validate_ipv46_address do not prohibit leading zero characters in octal literals. This may allow a bypass of access control that is based on IP addresses. (validate_ipv4_address and validate_ipv46_address are unaffected with Python 3.9.5+).
https://www.djangoproject.com/weblog/2021/jun/02/security-releases

Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to inefficient string concatenation when processing duplicate HTTP headers in ASGI mode. The ASGIRequest class combines repeated headers using repeated string concatenation, resulting in super-linear (quadratic) time complexity when processing requests with many duplicate headers.

Affected versions of the Django package are vulnerable to SQL Injection due to improper handling of column aliases containing periods in QuerySet.order_by() when combined with FilteredRelation. The QuerySet.order_by() method fails to properly sanitize column aliases that contain periods when the same alias is used in FilteredRelation via dictionary expansion. 
https://github.com/django/django/commit/90f5b10784ba5bf369caed87640e2b4394ea3314

Django 2.2.21, 3.1.9 and 3.2.1 include a fix for CVE-2021-31542: MultiPartParser, UploadedFile, and FieldFile allowed directory traversal via uploaded files with suitably crafted file names.
https://www.djangoproject.com/weblog/2021/may/04/security-releases

An issue was discovered in Django 4.2 before 4.2.21, 5.1 before 5.1.9, and 5.2 before 5.2.1. The django.utils.html.strip_tags() function is vulnerable to a potential denial-of-service (slow performance) when processing inputs containing large sequences of incomplete HTML tags. The template filter striptags is also vulnerable, because it is built on top of strip_tags().

In Django 3.2 before 3.2.16, 4.0 before 4.0.8, and 4.1 before 4.1.2, internationalized URLs were subject to a potential denial of service attack via the locale parameter, which is treated as a regular expression.

Affected versions of Django are vulnerable to potential Denial of Service via certain inputs with a very large number of Unicode characters in django.utils.encoding.uri_to_iri().

Django 1.11.29, 2.2.11 and 3.0.4 includes a fix for CVE-2020-9402: Django 1.11 before 1.11.29, 2.2 before 2.2.11, and 3.0 before 3.0.4 allows SQL Injection if untrusted data is used as a tolerance parameter in GIS functions and aggregates on Oracle. By passing a suitably crafted tolerance to GIS functions and aggregates on Oracle, it was possible to break escaping and inject malicious SQL.
https://www.djangoproject.com/weblog/2020/mar/04/security-releases

Django affected versions are vulnerable to a potential SQL injection in the HasKey(lhs, rhs) lookup on Oracle databases. The vulnerability arises when untrusted data is directly used as the lhs value in the django.db.models.fields.json.HasKey lookup. However, applications using the jsonfield.has_key lookup with the __ syntax remain unaffected by this issue.

Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to quadratic time complexity during HTML parsing in text truncation methods. The django.utils.text.Truncator.chars() and Truncator.words() methods (with html=True), as well as the truncatechars_html and truncatewords_html template filters, exhibit quadratic time complexity when processing inputs containing a large number of unmatched HTML end tags.

Django versions 2.2.25, 3.1.14 and 3.2.10 include a fix for CVE-2021-44420: In Django 2.2 before 2.2.25, 3.1 before 3.1.14, and 3.2 before 3.2.10, HTTP requests for URLs with trailing newlines could bypass upstream access control based on URL paths.
https://www.djangoproject.com/weblog/2021/dec/07/security-releases/

Django 2.1.15 and 2.2.8 includes a fix for CVE-2019-19118: A Django model admin displaying inline related models, where the user has view-only permissions to a parent model but edit permissions to the inline model, would be presented with an editing UI, allowing POST requests, for updating the inline model. Directly editing the view-only parent model was not possible, but the parent model's save() method was called, triggering potential side effects, and causing pre and post-save signal handlers to be invoked. To resolve this, the Django admin is adjusted to require edit permissions on the parent model in order for inline models to be editable.

Django 1.11.27, 2.2.9 and 3.0.1 include a fix for CVE-2019-19844: Account takeover. A suitably crafted email address (that is equal to an existing user's email address after case transformation of Unicode characters) would allow an attacker to be sent a password reset token for the matched user account. One mitigation in the new releases is to send password reset tokens only to the registered user email address.

Django has a potential denial-of-service vulnerability in django.utils.html.urlize() and AdminURLFieldWidget. The urlize and urlizetrunc functions, along with AdminURLFieldWidget, are vulnerable to denial-of-service attacks when handling inputs with a very large number of Unicode characters.

Affected versions of Django are potentially vulnerable to denial-of-service via the get_supported_language_variant() method. This method was susceptible to a denial-of-service attack when used with very long strings containing specific characters. Exploiting this vulnerability could cause significant delays or crashes in the affected application, potentially leading to service disruption.

Django versions 2.2.19, 3.0.13 and 3.1.7 include a fix for CVE-2021-23336: Web cache poisoning via 'django.utils.http.limited_parse_qsl()'. Django contains a copy of 'urllib.parse.parse_qsl' which was added to backport some security fixes. A further security fix has been issued recently such that 'parse_qsl(' no longer allows using ';' as a query parameter separator by default.

Django 4.2.1, 4.1.9 and 3.2.19 include a fix for CVE-2023-31047: In Django 3.2 before 3.2.19, 4.x before 4.1.9, and 4.2 before 4.2.1, it was possible to bypass validation when using one form field to upload multiple files. This multiple upload has never been supported by forms.FileField or forms.ImageField (only the last uploaded file was validated). However, Django's "Uploading multiple files" documentation suggested otherwise.
https://www.djangoproject.com/weblog/2023/may/03/security-releases

Affected versions of Django are vulnerable to potential regular expression denial-of-service (REDoS). django.utils.text.Truncator.words() method (with html=True) and truncatewords_html template filter were subject to a potential regular expression denial-of-service attack using a suitably crafted string (follow up to CVE-2019-14232 and CVE-2023-43665).

Affected versions of Django are vulnerable to a potential ReDoS (regular expression denial of service) in EmailValidator and URLValidator via a very large number of domain name labels of emails and URLs.

Django 2.2.27, 3.2.12 and 4.0.2 include a fix for CVE-2022-23833: Denial-of-service possibility in file uploads.
https://www.djangoproject.com/weblog/2022/feb/01/security-releases

Django 2.2.28, 3.2.13 and 4.0.4 include a fix for CVE-2022-28346: An issue was discovered in Django 2.2 before 2.2.28, 3.2 before 3.2.13, and 4.0 before 4.0.4. QuerySet.annotate(), aggregate(), and extra() methods are subject to SQL injection in column aliases via a crafted dictionary (with dictionary expansion) as the passed **kwargs.
https://www.djangoproject.com/weblog/2022/apr/11/security-releases

In Django 2.2 before 2.2.20, 3.0 before 3.0.14, and 3.1 before 3.1.8, MultiPartParser allowed directory traversal via uploaded files with suitably crafted file names. Built-in upload handlers were not affected by this vulnerability.

CVE-2025-64458: Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to slow Unicode NFKC normalization on Windows being applied to untrusted inputs. The django.contrib.auth.views.LoginView and django.contrib.auth.views.LogoutView, and django.views.i18n.set_language normalize user-controlled strings using Python’s NFKC algorithm, which is unusually slow on Windows for huge Unicode sequences and can be triggered to consume excessive CPU.

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45452: Storage.save in Django 2.2 before 2.2.26, 3.2 before 3.2.11, and 4.0 before 4.0.1 allows directory traversal if crafted filenames are directly passed to it.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases/

Affected versions of Django are vulnerable to a potential denial-of-service (DoS) attack in the `django.utils.html.strip_tags()` method. The vulnerability occurs when the `strip_tags()` method or the `striptags` template filter processes inputs containing large sequences of nested, incomplete HTML entities.

Affected versions of the Django package are vulnerable to Information Disclosure (Timing Attack) due to non-constant-time comparison in the mod_wsgi authentication handler. The django.contrib.auth.handlers.modwsgi.check_password() function does not perform user existence checks in constant time, allowing response timing differences to reveal whether usernames exist.

The {% debug %} template tag in Django 2.2 before 2.2.27, 3.2 before 3.2.12, and 4.0 before 4.0.2 does not properly encode the current context. This may lead to XSS.

Django fixes a potential denial-of-service vulnerability in XML ``Deserializer``.

An issue was discovered in Django 5.2 before 5.2.3, 5.1 before 5.1.11, and 4.2 before 4.2.23. Internal HTTP response logging does not escape request.path, which allows remote attackers to potentially manipulate log output via crafted URLs. This may lead to log injection or forgery when logs are viewed in terminals or processed by external systems.

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45116: An issue was discovered in Django 2.2 before 2.2.26, 3.2 before 3.2.11, and 4.0 before 4.0.1. Due to leveraging the Django Template Language's variable resolution logic, the dictsort template filter was potentially vulnerable to information disclosure, or an unintended method call, if passed a suitably crafted key.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45115: UserAttributeSimilarityValidator incurred significant overhead in evaluating a submitted password that was artificially large in relation to the comparison values. In a situation where access to user registration was unrestricted, this provided a potential vector for a denial-of-service attack.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases/

Affected versions of Django are affected by a potential denial-of-service vulnerability in the django.utils.html.urlize() function. The urlize and urlizetrunc template filters were susceptible to a denial-of-service attack via certain inputs containing many brackets. An attacker could exploit this vulnerability to cause significant delays or crashes in the affected application.

Affected versions of Django are affected by a directory-traversal vulnerability in the Storage.save() method. Derived classes of the django.core.files.storage.Storage base class that overrides the generate_filename() method without replicating the file path validations existing in the parent class could allow for directory traversal via certain inputs when calling save(). This could enable an attacker to manipulate file paths and access unintended directories.

Django 1.11.28, 2.2.10 and 3.0.3 include a fix for CVE-2020-7471: SQL Injection if untrusted data is used as a StringAgg delimiter (e.g., in Django applications that offer downloads of data as a series of rows with a user-specified column delimiter). By passing a suitably crafted delimiter to a contrib.postgres.aggregates.StringAgg instance, it was possible to break escaping and inject malicious SQL.

Affected versions of Django has a potential SQL injection vulnerability in the QuerySet.values() and QuerySet.values_list() methods. When used on models with a JSONField, these methods are susceptible to SQL injection through column aliases if a crafted JSON object key is passed as an argument.

A security vulnerability has been discovered in certain versions of Django, affecting the password reset functionality. The PasswordResetForm class in django.contrib.auth.forms inadvertently allowed attackers to enumerate user email addresses by exploiting unhandled exceptions during the email sending process. This could be done by issuing password reset requests and observing the responses. Django has implemented a fix where these exceptions are now caught and logged using the django.contrib.auth logger, preventing potential information leakage through error responses.

Django 2.2.18, 3.0.12 and 3.1.6 include a fix for CVE-2021-3281: The django.utils.archive.extract method (used by "startapp --template" and "startproject --template") allows directory traversal via an archive with absolute paths or relative paths with dot segments.

Django 4.2.7, 4.1.13 and 3.2.23 include a fix for CVE-2023-46695: Potential denial of service vulnerability in UsernameField on Windows.
https://www.djangoproject.com/weblog/2023/nov/01/security-releases

Affected versions of Django are vulnerable to Denial-of-Service via django.utils.text.Truncator. The django.utils.text.Truncator chars() and words() methods (when used with html=True) are subject to a potential DoS (denial of service) attack via certain inputs with very long, potentially malformed HTML text. The chars() and words() methods are used to implement the truncatechars_html and truncatewords_html template filters, which are thus also vulnerable. NOTE: this issue exists because of an incomplete fix for CVE-2019-14232.

Affected versions of Django are affected by a username enumeration vulnerability caused by timing differences in the django.contrib.auth.backends.ModelBackend.authenticate() method. This method allowed remote attackers to enumerate users through a timing attack involving login requests for users with unusable passwords. The timing difference in the authentication process exposed whether a username was valid or not, potentially aiding attackers in gaining unauthorized access.

Django 2.2.28, 3.2.13 and 4.0.4 include a fix for CVE-2022-28347: A SQL injection issue was discovered in QuerySet.explain() in Django 2.2 before 2.2.28, 3.2 before 3.2.13, and 4.0 before 4.0.4. This occurs by passing a crafted dictionary (with dictionary expansion) as the **options argument, and placing the injection payload in an option name.
https://www.djangoproject.com/weblog/2022/apr/11/security-releases

Django 2.2.16, 3.0.10 and 3.1.1 include a fix for CVE-2020-24583: An issue was discovered in Django 2.2 before 2.2.16, 3.0 before 3.0.10, and 3.1 before 3.1.1 (when Python 3.7+ is used). FILE_UPLOAD_DIRECTORY_PERMISSIONS mode was not applied to intermediate-level directories created in the process of uploading files. It was also not applied to intermediate-level collected static directories when using the collectstatic management command.
#NOTE: This vulnerability affects only users of Python versions above 3.7.
https://www.djangoproject.com/weblog/2020/sep/01/security-releases

Django 3.2.17, 4.0.9 and 4.1.6 includes a fix for CVE-2023-23969: In Django 3.2 before 3.2.17, 4.0 before 4.0.9, and 4.1 before 4.1.6, the parsed values of Accept-Language headers are cached in order to avoid repetitive parsing. This leads to a potential denial-of-service vector via excessive memory usage if the raw value of Accept-Language headers is very large.
https://www.djangoproject.com/weblog/2023/feb/01/security-releases

Affected versions of the `django` package are vulnerable to Download of Code Without Integrity Check due to improper handling of user-supplied input in the HTTP FileResponse class. The vulnerability arises because the Content-Disposition header of a FileResponse can be set using a filename derived from user input without sufficient validation. An attacker can exploit this by crafting a request that causes a file with malicious content to be downloaded, potentially executing arbitrary code on the client system when the file is opened.

CVE-2025-64459: Affected versions of the Django package are vulnerable to SQL Injection due to improper input validation, allowing the internal _connector keyword argument to be accepted from untrusted dictionaries via expansion. The .filter(), .exclude(), and .get() methods on QuerySet, as well as the Q class, resolve **kwargs and will treat a supplied _connector value as the logical connector without constraining it to the expected set (AND/OR), permitting attacker-controlled tokens to influence SQL predicate construction.

Affected versions of the Django package are vulnerable to SQL Injection due to insufficient input sanitization in FilteredRelation column aliases. The FilteredRelation class fails to properly validate or escape column alias names when they are provided through dictionary expansion as keyword arguments to QuerySet.annotate() or QuerySet.alias() methods, allowing malicious SQL code to be injected directly into the generated database queries.

Django fixes potential SQL injection in ``FilteredRelation`` column aliases on PostgreSQL.

Affected versions of the sqlparse package are vulnerable to Denial of Service (DoS) due to missing hard limits on token grouping recursion depth and token processing when formatting very large SQL tuple lists. During sqlparse.format() processing, the sqlparse.engine.grouping._group_matching() and sqlparse.engine.grouping._group() functions can recurse and iterate over excessively large tlist.tokens without enforcing MAX_GROUPING_DEPTH or MAX_GROUPING_TOKENS, allowing grouping work to grow until it effectively hangs.

Affected versions of this package are vulnerable to Denial of Service (DoS) attacks due to Algorithmic Complexity. The SQL parser fails to enforce limits when processing deeply nested tuples and large token sequences, leading to excessive resource consumption through crafted SQL statements with extreme nesting depth or token counts.

**Note:** This issue is due to an incomplete fix for CVE-2024-4340.

Sqlparse 0.5.0 addresses a potential denial of service (DoS) vulnerability related to recursion errors in deeply nested SQL statements. To mitigate this issue, the update replaces recursion errors with a general SQLParseError, improving the resilience and stability of the parsing process.

Sqlparse 0.4.4 includes a fix for CVE-2023-30608: Parser contains a regular expression that is vulnerable to ReDOS (Regular Expression Denial of Service).
https://github.com/andialbrecht/sqlparse/security/advisories/GHSA-rrm6-wvj7-cwh2

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to redirect handling that drains connections by decompressing redirect response bodies without enforcing streaming read limits. The issue occurs when using urllib3’s streaming mode (for example, preload_content=False) while allowing redirects, because urllib3.response.HTTPResponse.drain_conn() would call HTTPResponse.read() in a way that decoded/decompressed the entire redirect response body even before any streaming reads were performed, effectively bypassing decompression-bomb safeguards.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to improper handling of highly compressed HTTP response bodies during streaming decompression. The urllib3.HTTPResponse methods stream(), read(), read1(), read_chunked(), and readinto() may fully decompress a minimal but highly compressed payload based on the Content-Encoding header into an internal buffer instead of limiting the decompressed output to the requested chunk size, causing excessive CPU usage and massive memory allocation on the client side.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to allowing an unbounded number of content-encoding decompression steps for HTTP responses. The HTTPResponse content decoding pipeline in urllib3 follows the Content-Encoding header and applies each advertised compression algorithm in sequence without enforcing a maximum chain length or effective output size, so a malicious peer can send a response with a very long encoding chain that triggers excessive CPU use and massive memory allocation during decompression.

Urllib3's ProxyManager ensures that the Proxy-Authorization header is correctly directed only to configured proxies. However, when HTTP requests bypass urllib3's proxy support, there's a risk of inadvertently setting the Proxy-Authorization header, which remains ineffective without a forwarding or tunneling proxy. Urllib3 does not recognize this header as carrying authentication data, failing to remove it during cross-origin redirects. While this scenario is uncommon and poses low risk to most users, urllib3 now proactively removes the Proxy-Authorization header during cross-origin redirects as a precautionary measure. Users are advised to utilize urllib3's proxy support or disable automatic redirects to handle the Proxy-Authorization header securely. Despite these precautions, urllib3 defaults to stripping the header to safeguard users who may inadvertently misconfigure requests.

Urllib3 1.26.17 and 2.0.5 include a fix for CVE-2023-43804: Urllib3 doesn't treat the 'Cookie' HTTP header special or provide any helpers for managing cookies over HTTP, that is the responsibility of the user. However, it is possible for a user to specify a 'Cookie' header and unknowingly leak information via HTTP redirects to a different origin if that user doesn't disable redirects explicitly.
https://github.com/urllib3/urllib3/security/advisories/GHSA-v845-jxx5-vc9f

Urllib3 1.26.5 includes a fix for CVE-2021-33503: When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking, causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redirect.
https://github.com/advisories/GHSA-q2q7-5pp4-w6pg

The _encode_invalid_chars function in util/url.py in the urllib3 library 1.25.2 through 1.25.7 for Python allows a denial of service (CPU consumption) because of an inefficient algorithm. The percent_encodings array contains all matches of percent encodings. It is not deduplicated. For a URL of length N, the size of percent_encodings may be up to O(N). The next step (normalize existing percent-encoded bytes) also takes up to O(N) for each step, so the total time is O(N^2). If percent_encodings were deduplicated, the time to compute _encode_invalid_chars would be O(kN), where k is at most 484 ((10+6*2)^2). See: CVE-2020-7212.

Affected versions of urllib3 are vulnerable to an HTTP redirect handling vulnerability that fails to remove the HTTP request body when a POST changes to a GET via 301, 302, or 303 responses. This flaw can expose sensitive request data if the origin service is compromised and redirects to a malicious endpoint, though exploitability is low when no sensitive data is used. The vulnerability affects automatic redirect behavior. It is fixed in versions 1.26.18 and 2.0.7; update or disable redirects using redirects=False.
This vulnerability is specific to Python's urllib3 library.

urllib3 is a user-friendly HTTP client library for Python. Prior to 2.5.0, it is possible to disable redirects for all requests by instantiating a PoolManager and specifying retries in a way that disable redirects. By default, requests and botocore users are not affected. An application attempting to mitigate SSRF or open redirect vulnerabilities by disabling redirects at the PoolManager level will remain vulnerable. This issue has been patched in version 2.5.0.

Urllib3 1.25.9 includes a fix for CVE-2020-26137: Urllib3 before 1.25.9 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserting CR and LF control characters in the first argument of putrequest(). NOTE: this is similar to CVE-2020-26116.
https://github.com/python/cpython/issues/83784
https://github.com/urllib3/urllib3/pull/1800

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to redirect handling that drains connections by decompressing redirect response bodies without enforcing streaming read limits. The issue occurs when using urllib3’s streaming mode (for example, preload_content=False) while allowing redirects, because urllib3.response.HTTPResponse.drain_conn() would call HTTPResponse.read() in a way that decoded/decompressed the entire redirect response body even before any streaming reads were performed, effectively bypassing decompression-bomb safeguards.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to improper handling of highly compressed HTTP response bodies during streaming decompression. The urllib3.HTTPResponse methods stream(), read(), read1(), read_chunked(), and readinto() may fully decompress a minimal but highly compressed payload based on the Content-Encoding header into an internal buffer instead of limiting the decompressed output to the requested chunk size, causing excessive CPU usage and massive memory allocation on the client side.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to allowing an unbounded number of content-encoding decompression steps for HTTP responses. The HTTPResponse content decoding pipeline in urllib3 follows the Content-Encoding header and applies each advertised compression algorithm in sequence without enforcing a maximum chain length or effective output size, so a malicious peer can send a response with a very long encoding chain that triggers excessive CPU use and massive memory allocation during decompression.

Urllib3's ProxyManager ensures that the Proxy-Authorization header is correctly directed only to configured proxies. However, when HTTP requests bypass urllib3's proxy support, there's a risk of inadvertently setting the Proxy-Authorization header, which remains ineffective without a forwarding or tunneling proxy. Urllib3 does not recognize this header as carrying authentication data, failing to remove it during cross-origin redirects. While this scenario is uncommon and poses low risk to most users, urllib3 now proactively removes the Proxy-Authorization header during cross-origin redirects as a precautionary measure. Users are advised to utilize urllib3's proxy support or disable automatic redirects to handle the Proxy-Authorization header securely. Despite these precautions, urllib3 defaults to stripping the header to safeguard users who may inadvertently misconfigure requests.

Urllib3 1.26.17 and 2.0.5 include a fix for CVE-2023-43804: Urllib3 doesn't treat the 'Cookie' HTTP header special or provide any helpers for managing cookies over HTTP, that is the responsibility of the user. However, it is possible for a user to specify a 'Cookie' header and unknowingly leak information via HTTP redirects to a different origin if that user doesn't disable redirects explicitly.
https://github.com/urllib3/urllib3/security/advisories/GHSA-v845-jxx5-vc9f

Urllib3 1.26.5 includes a fix for CVE-2021-33503: When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking, causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redirect.
https://github.com/advisories/GHSA-q2q7-5pp4-w6pg

The _encode_invalid_chars function in util/url.py in the urllib3 library 1.25.2 through 1.25.7 for Python allows a denial of service (CPU consumption) because of an inefficient algorithm. The percent_encodings array contains all matches of percent encodings. It is not deduplicated. For a URL of length N, the size of percent_encodings may be up to O(N). The next step (normalize existing percent-encoded bytes) also takes up to O(N) for each step, so the total time is O(N^2). If percent_encodings were deduplicated, the time to compute _encode_invalid_chars would be O(kN), where k is at most 484 ((10+6*2)^2). See: CVE-2020-7212.

Affected versions of urllib3 are vulnerable to an HTTP redirect handling vulnerability that fails to remove the HTTP request body when a POST changes to a GET via 301, 302, or 303 responses. This flaw can expose sensitive request data if the origin service is compromised and redirects to a malicious endpoint, though exploitability is low when no sensitive data is used. The vulnerability affects automatic redirect behavior. It is fixed in versions 1.26.18 and 2.0.7; update or disable redirects using redirects=False.
This vulnerability is specific to Python's urllib3 library.

urllib3 is a user-friendly HTTP client library for Python. Prior to 2.5.0, it is possible to disable redirects for all requests by instantiating a PoolManager and specifying retries in a way that disable redirects. By default, requests and botocore users are not affected. An application attempting to mitigate SSRF or open redirect vulnerabilities by disabling redirects at the PoolManager level will remain vulnerable. This issue has been patched in version 2.5.0.

Urllib3 1.25.9 includes a fix for CVE-2020-26137: Urllib3 before 1.25.9 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserting CR and LF control characters in the first argument of putrequest(). NOTE: this is similar to CVE-2020-26116.
https://github.com/python/cpython/issues/83784
https://github.com/urllib3/urllib3/pull/1800

Affected versions of the gunicorn package are vulnerable to HTTP Request/Response Smuggling due to improper validation of the Transfer-Encoding header that enables a TE.CL desynchronisation condition. Gunicorn’s HTTP parser does not consistently enforce RFC semantics when parsing conflicting or unsupported request framing—such as messages containing both Transfer-Encoding and Content-Length—so the backend may fall back to Content-Length while an intermediary treats the message as chunked.

Gunicorn 20.0.1 fixes chunked encoding support to prevent http request smuggling attacks.
https://github.com/benoitc/gunicorn/issues/2176
https://github.com/p4k03n4t0r/http-request-smuggling#request-smuggling-using-mitmproxy-and-gunicorn

Gunicorn fails to properly validate Transfer-Encoding headers, leading to HTTP Request Smuggling (HRS) vulnerabilities. By crafting requests with conflicting Transfer-Encoding headers, attackers can bypass security restrictions and access restricted endpoints. This issue is due to Gunicorn's handling of Transfer-Encoding headers, where it incorrectly processes requests with multiple, conflicting Transfer-Encoding headers, treating them as chunked regardless of the final encoding specified. This vulnerability allows for a range of attacks including cache poisoning, session manipulation, and data exposure.

Requests is an HTTP library. Due to a URL parsing issue, Requests releases prior to 2.32.4 may leak .netrc credentials to third parties for specific maliciously-crafted URLs. Users should upgrade to version 2.32.4 to receive a fix. For older versions of Requests, use of the .netrc file can be disabled with `trust_env=False` on one's Requests Session.

Affected versions of Requests are vulnerable to proxy credential leakage. When redirected to an HTTPS endpoint, the Proxy-Authorization header is forwarded to the destination server due to the use of rebuild_proxies to reattach the header. This may allow a malicious actor to exfiltrate sensitive information.

Affected versions of the requests package are vulnerable to Insecure Temporary File reuse due to predictable temporary filename generation in extract_zipped_paths(). The requests.utils.extract_zipped_paths() utility extracts files from zip archives into the system temporary directory using a deterministic path, and if that file already exists, the function reuses it without validating that it is the expected extracted content.

Affected versions of Requests, when making requests through a Requests `Session`, if the first request is made with `verify=False` to disable cert verification, all subsequent requests to the same host will continue to ignore cert verification regardless of changes to the value of `verify`. This behavior will continue for the lifecycle of the connection in the connection pool. Requests 2.32.0 fixes the issue, but versions 2.32.0 and 2.32.1 were yanked due to conflicts with CVE-2024-35195 mitigation.

Certifi 2022.12.07 includes a fix for CVE-2022-23491: Certifi 2022.12.07 removes root certificates from "TrustCor" from the root store. These are in the process of being removed from Mozilla's trust store. TrustCor's root certificates are being removed pursuant to an investigation prompted by media reporting that TrustCor's ownership also operated a business that produced spyware. Conclusions of Mozilla's investigation can be found in the linked google group discussion.

Certifi 2023.07.22 includes a fix for CVE-2023-37920: Certifi prior to version 2023.07.22 recognizes "e-Tugra" root certificates. e-Tugra's root certificates were subject to an investigation prompted by reporting of security issues in their systems. Certifi 2023.07.22 removes root certificates from "e-Tugra" from the root store.
https://github.com/certifi/python-certifi/security/advisories/GHSA-xqr8-7jwr-rhp7

Certifi 2022.12.07 includes a fix for CVE-2022-23491: Certifi 2022.12.07 removes root certificates from "TrustCor" from the root store. These are in the process of being removed from Mozilla's trust store. TrustCor's root certificates are being removed pursuant to an investigation prompted by media reporting that TrustCor's ownership also operated a business that produced spyware. Conclusions of Mozilla's investigation can be found in the linked google group discussion.

Certifi 2023.07.22 includes a fix for CVE-2023-37920: Certifi prior to version 2023.07.22 recognizes "e-Tugra" root certificates. e-Tugra's root certificates were subject to an investigation prompted by reporting of security issues in their systems. Certifi 2023.07.22 removes root certificates from "e-Tugra" from the root store.
https://github.com/certifi/python-certifi/security/advisories/GHSA-xqr8-7jwr-rhp7

Affected versions of Sentry's Python SDK are vulnerable to unintentional exposure of environment variables to subprocesses despite the env={} setting. In Python's 'subprocess' calls, all environment variables are passed to subprocesses by default. However, if you specifically do not want them to be passed to subprocesses, you may use 'env' argument in 'subprocess' calls. Due to the bug in Sentry SDK, with the Stdlib integration enabled (which is enabled by default), this expectation is not fulfilled, and all environment variables are being passed to subprocesses instead. 
As a workaround, and if passing environment variables to child processes poses a security risk for you, you can disable all default integrations.

Sentry-sdk 1.14.0 includes a fix for CVE-2023-28117: When using the Django integration of versions prior to 1.14.0 of the Sentry SDK in a specific configuration it is possible to leak sensitive cookies values, including the session cookie to Sentry. These sensitive cookies could then be used by someone with access to your Sentry issues to impersonate or escalate their privileges within your application. In order for these sensitive values to be leaked, the Sentry SDK configuration must have 'sendDefaultPII' set to 'True'; one must use a custom name for either 'SESSION_COOKIE_NAME' or 'CSRF_COOKIE_NAME' in one's Django settings; and one must not be configured in one's organization or project settings to use Sentry's data scrubbing features to account for the custom cookie names. As of version 1.14.0, the Django integration of the 'sentry-sdk' will detect the custom cookie names based on one's Django settings and will remove the values from the payload before sending the data to Sentry. As a workaround, use the SDK's filtering mechanism to remove the cookies from the payload that is sent to Sentry. For error events, this can be done with the 'before_send' callback method and for performance related events (transactions) one can use the 'before_send_transaction' callback method. Those who want to handle filtering of these values on the server-side can also use Sentry's advanced data scrubbing feature to account for the custom cookie names. Look for the '$http.cookies', '$http.headers', '$request.cookies', or '$request.headers' fields to target with a scrubbing rule.
https://github.com/getsentry/sentry-python/security/advisories/GHSA-29pr-6jr8-q5jm

Sentry-sdk 1.4.1 includes a fix for a Race Condition vulnerability.
https://github.com/getsentry/sentry-python/pull/1203

A SQL Injection issue in the SQL Panel in Jazzband Django Debug Toolbar before 1.11.1, 2.x before 2.2.1, and 3.x before 3.2.1 allows attackers to execute SQL statements by changing the raw_sql input field of the SQL explain, analyze, or select form. See CVE-2021-30459.

** DISPUTED ** Py throughout 1.11.0 allows remote attackers to conduct a ReDoS (Regular expression Denial of Service) attack via a Subversion repository with crafted info data because the InfoSvnCommand argument is mishandled.
https://github.com/pytest-dev/py/issues/287

Py 1.10.0 includes a fix for CVE-2020-29651: A denial of service via regular expression in the py.path.svnwc component of py (aka python-py) through 1.9.0 could be used by attackers to cause a compute-time denial of service attack by supplying malicious input to the blame functionality.

Affected versions of Idna are vulnerable to Denial Of Service via the idna.encode(), where a specially crafted argument could lead to significant resource consumption. In version 3.7, this function has been updated to reject such inputs efficiently, minimizing resource use. A practical workaround involves enforcing a maximum domain name length of 253 characters before encoding, as the vulnerability is triggered by unusually large inputs that normal operations wouldn't encounter.

** DISPUTED ** Py throughout 1.11.0 allows remote attackers to conduct a ReDoS (Regular expression Denial of Service) attack via a Subversion repository with crafted info data because the InfoSvnCommand argument is mishandled.
https://github.com/pytest-dev/py/issues/287

Py 1.10.0 includes a fix for CVE-2020-29651: A denial of service via regular expression in the py.path.svnwc component of py (aka python-py) through 1.9.0 could be used by attackers to cause a compute-time denial of service attack by supplying malicious input to the blame functionality.

An issue was discovered in Django 2.2 before 2.2.13 and 3.0 before 3.0.7. Query parameters generated by the Django admin ForeignKeyRawIdWidget were not properly URL encoded, leading to a possibility of an XSS attack.

Affected versions of the Django package are vulnerable to SQL Injection due to improper handling of control characters in column aliases within FilteredRelation. The FilteredRelation class fails to properly sanitize column aliases containing control characters when used with QuerySet methods annotate(), aggregate(), extra(), values(), values_list(), and alias() via dictionary expansion (**kwargs).

Affected versions of the Django package are vulnerable to SQL Injection due to improper sanitization of band index parameters in PostGIS raster lookups. The raster lookup functionality in Django's GIS module fails to properly validate or escape untrusted data used as a band index when performing spatial queries against PostGIS databases.

Affected versions of Django are vulnerable to potential denial-of-service in intcomma template filter when used with very long strings.

A potential denial-of-service vulnerability has been identified in Django's urlize() and urlizetrunc() functions in django.utils.html. This vulnerability can be triggered by inputting huge strings containing a specific sequence of characters.

Django 3.2.14 and 4.0.6 include a fix for CVE-2022-34265: Potential SQL injection via Trunc(kind) and Extract(lookup_name) arguments.
https://www.djangoproject.com/weblog/2022/jul/04/security-releases

An issue was discovered in Django 2.2 before 2.2.13 and 3.0 before 3.0.7. In cases where a memcached backend does not perform key validation, passing malformed cache keys could result in a key collision, and potential data leakage.

Django 4.1.7, 4.0.10 and 3.2.18 include a fix for CVE-2023-24580: Potential denial-of-service vulnerability in file uploads.
https://www.djangoproject.com/weblog/2023/feb/14/security-releases

An issue was discovered in Django 2.2 before 2.2.16, 3.0 before 3.0.10, and 3.1 before 3.1.1 (when Python 3.7+ is used). The intermediate-level directories of the filesystem cache had the system's standard umask rather than 0o077.

Django versions 3.2.2, 3.1.10 and 2.2.22 include a fix for CVE-2021-32052: In Django 2.2 before 2.2.22, 3.1 before 3.1.10, and 3.2 before 3.2.2 (with Python 3.9.5+), URLValidator does not prohibit newlines and tabs (unless the URLField form field is used). If an application uses values with newlines in an HTTP response, header injection can occur. Django itself is unaffected because HttpResponse prohibits newlines in HTTP headers.
https://www.djangoproject.com/weblog/2021/may/06/security-releases

Affected versions of the Django package are vulnerable to Path Traversal due to improper validation of file paths in the django.contrib.admindocs module. The `TemplateDetailView` view allows staff members to verify the existence of arbitrary files by manipulating the file path. An attacker with staff privileges can exploit this vulnerability to check for the presence of files outside the template root directories, and if the `admindocs` templates are customized to display file contents, they can also access the contents of these files.

Django addresses a memory exhaustion issue in django.utils.numberformat.floatformat(). When floatformat receives a string representation of a number in scientific notation with a large exponent, it could lead to excessive memory consumption. To prevent this, decimals with more than 200 digits are now returned as-is.

Django 2.2.24, 3.1.12, and 3.2.4 include a fix for CVE-2021-33571: In Django 2.2 before 2.2.24, 3.x before 3.1.12, and 3.2 before 3.2.4, URLValidator, validate_ipv4_address, and validate_ipv46_address do not prohibit leading zero characters in octal literals. This may allow a bypass of access control that is based on IP addresses. (validate_ipv4_address and validate_ipv46_address are unaffected with Python 3.9.5+).
https://www.djangoproject.com/weblog/2021/jun/02/security-releases

Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to inefficient string concatenation when processing duplicate HTTP headers in ASGI mode. The ASGIRequest class combines repeated headers using repeated string concatenation, resulting in super-linear (quadratic) time complexity when processing requests with many duplicate headers.

Affected versions of the Django package are vulnerable to SQL Injection due to improper handling of column aliases containing periods in QuerySet.order_by() when combined with FilteredRelation. The QuerySet.order_by() method fails to properly sanitize column aliases that contain periods when the same alias is used in FilteredRelation via dictionary expansion. 
https://github.com/django/django/commit/90f5b10784ba5bf369caed87640e2b4394ea3314

Django 2.2.21, 3.1.9 and 3.2.1 include a fix for CVE-2021-31542: MultiPartParser, UploadedFile, and FieldFile allowed directory traversal via uploaded files with suitably crafted file names.
https://www.djangoproject.com/weblog/2021/may/04/security-releases

An issue was discovered in Django 4.2 before 4.2.21, 5.1 before 5.1.9, and 5.2 before 5.2.1. The django.utils.html.strip_tags() function is vulnerable to a potential denial-of-service (slow performance) when processing inputs containing large sequences of incomplete HTML tags. The template filter striptags is also vulnerable, because it is built on top of strip_tags().

In Django 3.2 before 3.2.16, 4.0 before 4.0.8, and 4.1 before 4.1.2, internationalized URLs were subject to a potential denial of service attack via the locale parameter, which is treated as a regular expression.

Affected versions of Django are vulnerable to potential Denial of Service via certain inputs with a very large number of Unicode characters in django.utils.encoding.uri_to_iri().

Django 1.11.29, 2.2.11 and 3.0.4 includes a fix for CVE-2020-9402: Django 1.11 before 1.11.29, 2.2 before 2.2.11, and 3.0 before 3.0.4 allows SQL Injection if untrusted data is used as a tolerance parameter in GIS functions and aggregates on Oracle. By passing a suitably crafted tolerance to GIS functions and aggregates on Oracle, it was possible to break escaping and inject malicious SQL.
https://www.djangoproject.com/weblog/2020/mar/04/security-releases

Django affected versions are vulnerable to a potential SQL injection in the HasKey(lhs, rhs) lookup on Oracle databases. The vulnerability arises when untrusted data is directly used as the lhs value in the django.db.models.fields.json.HasKey lookup. However, applications using the jsonfield.has_key lookup with the __ syntax remain unaffected by this issue.

Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to quadratic time complexity during HTML parsing in text truncation methods. The django.utils.text.Truncator.chars() and Truncator.words() methods (with html=True), as well as the truncatechars_html and truncatewords_html template filters, exhibit quadratic time complexity when processing inputs containing a large number of unmatched HTML end tags.

Django versions 2.2.25, 3.1.14 and 3.2.10 include a fix for CVE-2021-44420: In Django 2.2 before 2.2.25, 3.1 before 3.1.14, and 3.2 before 3.2.10, HTTP requests for URLs with trailing newlines could bypass upstream access control based on URL paths.
https://www.djangoproject.com/weblog/2021/dec/07/security-releases/

Django 2.1.15 and 2.2.8 includes a fix for CVE-2019-19118: A Django model admin displaying inline related models, where the user has view-only permissions to a parent model but edit permissions to the inline model, would be presented with an editing UI, allowing POST requests, for updating the inline model. Directly editing the view-only parent model was not possible, but the parent model's save() method was called, triggering potential side effects, and causing pre and post-save signal handlers to be invoked. To resolve this, the Django admin is adjusted to require edit permissions on the parent model in order for inline models to be editable.

Django 1.11.27, 2.2.9 and 3.0.1 include a fix for CVE-2019-19844: Account takeover. A suitably crafted email address (that is equal to an existing user's email address after case transformation of Unicode characters) would allow an attacker to be sent a password reset token for the matched user account. One mitigation in the new releases is to send password reset tokens only to the registered user email address.

Django has a potential denial-of-service vulnerability in django.utils.html.urlize() and AdminURLFieldWidget. The urlize and urlizetrunc functions, along with AdminURLFieldWidget, are vulnerable to denial-of-service attacks when handling inputs with a very large number of Unicode characters.

Affected versions of Django are potentially vulnerable to denial-of-service via the get_supported_language_variant() method. This method was susceptible to a denial-of-service attack when used with very long strings containing specific characters. Exploiting this vulnerability could cause significant delays or crashes in the affected application, potentially leading to service disruption.

Django versions 2.2.19, 3.0.13 and 3.1.7 include a fix for CVE-2021-23336: Web cache poisoning via 'django.utils.http.limited_parse_qsl()'. Django contains a copy of 'urllib.parse.parse_qsl' which was added to backport some security fixes. A further security fix has been issued recently such that 'parse_qsl(' no longer allows using ';' as a query parameter separator by default.

Django 4.2.1, 4.1.9 and 3.2.19 include a fix for CVE-2023-31047: In Django 3.2 before 3.2.19, 4.x before 4.1.9, and 4.2 before 4.2.1, it was possible to bypass validation when using one form field to upload multiple files. This multiple upload has never been supported by forms.FileField or forms.ImageField (only the last uploaded file was validated). However, Django's "Uploading multiple files" documentation suggested otherwise.
https://www.djangoproject.com/weblog/2023/may/03/security-releases

Affected versions of Django are vulnerable to potential regular expression denial-of-service (REDoS). django.utils.text.Truncator.words() method (with html=True) and truncatewords_html template filter were subject to a potential regular expression denial-of-service attack using a suitably crafted string (follow up to CVE-2019-14232 and CVE-2023-43665).

Affected versions of Django are vulnerable to a potential ReDoS (regular expression denial of service) in EmailValidator and URLValidator via a very large number of domain name labels of emails and URLs.

Django 2.2.27, 3.2.12 and 4.0.2 include a fix for CVE-2022-23833: Denial-of-service possibility in file uploads.
https://www.djangoproject.com/weblog/2022/feb/01/security-releases

Django 2.2.28, 3.2.13 and 4.0.4 include a fix for CVE-2022-28346: An issue was discovered in Django 2.2 before 2.2.28, 3.2 before 3.2.13, and 4.0 before 4.0.4. QuerySet.annotate(), aggregate(), and extra() methods are subject to SQL injection in column aliases via a crafted dictionary (with dictionary expansion) as the passed **kwargs.
https://www.djangoproject.com/weblog/2022/apr/11/security-releases

In Django 2.2 before 2.2.20, 3.0 before 3.0.14, and 3.1 before 3.1.8, MultiPartParser allowed directory traversal via uploaded files with suitably crafted file names. Built-in upload handlers were not affected by this vulnerability.

CVE-2025-64458: Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to slow Unicode NFKC normalization on Windows being applied to untrusted inputs. The django.contrib.auth.views.LoginView and django.contrib.auth.views.LogoutView, and django.views.i18n.set_language normalize user-controlled strings using Python’s NFKC algorithm, which is unusually slow on Windows for huge Unicode sequences and can be triggered to consume excessive CPU.

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45452: Storage.save in Django 2.2 before 2.2.26, 3.2 before 3.2.11, and 4.0 before 4.0.1 allows directory traversal if crafted filenames are directly passed to it.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases/

Affected versions of Django are vulnerable to a potential denial-of-service (DoS) attack in the `django.utils.html.strip_tags()` method. The vulnerability occurs when the `strip_tags()` method or the `striptags` template filter processes inputs containing large sequences of nested, incomplete HTML entities.

Affected versions of the Django package are vulnerable to Information Disclosure (Timing Attack) due to non-constant-time comparison in the mod_wsgi authentication handler. The django.contrib.auth.handlers.modwsgi.check_password() function does not perform user existence checks in constant time, allowing response timing differences to reveal whether usernames exist.

The {% debug %} template tag in Django 2.2 before 2.2.27, 3.2 before 3.2.12, and 4.0 before 4.0.2 does not properly encode the current context. This may lead to XSS.

Django fixes a potential denial-of-service vulnerability in XML ``Deserializer``.

An issue was discovered in Django 5.2 before 5.2.3, 5.1 before 5.1.11, and 4.2 before 4.2.23. Internal HTTP response logging does not escape request.path, which allows remote attackers to potentially manipulate log output via crafted URLs. This may lead to log injection or forgery when logs are viewed in terminals or processed by external systems.

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45116: An issue was discovered in Django 2.2 before 2.2.26, 3.2 before 3.2.11, and 4.0 before 4.0.1. Due to leveraging the Django Template Language's variable resolution logic, the dictsort template filter was potentially vulnerable to information disclosure, or an unintended method call, if passed a suitably crafted key.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45115: UserAttributeSimilarityValidator incurred significant overhead in evaluating a submitted password that was artificially large in relation to the comparison values. In a situation where access to user registration was unrestricted, this provided a potential vector for a denial-of-service attack.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases/

Affected versions of Django are affected by a potential denial-of-service vulnerability in the django.utils.html.urlize() function. The urlize and urlizetrunc template filters were susceptible to a denial-of-service attack via certain inputs containing many brackets. An attacker could exploit this vulnerability to cause significant delays or crashes in the affected application.

Affected versions of Django are affected by a directory-traversal vulnerability in the Storage.save() method. Derived classes of the django.core.files.storage.Storage base class that overrides the generate_filename() method without replicating the file path validations existing in the parent class could allow for directory traversal via certain inputs when calling save(). This could enable an attacker to manipulate file paths and access unintended directories.

Django 1.11.28, 2.2.10 and 3.0.3 include a fix for CVE-2020-7471: SQL Injection if untrusted data is used as a StringAgg delimiter (e.g., in Django applications that offer downloads of data as a series of rows with a user-specified column delimiter). By passing a suitably crafted delimiter to a contrib.postgres.aggregates.StringAgg instance, it was possible to break escaping and inject malicious SQL.

Affected versions of Django has a potential SQL injection vulnerability in the QuerySet.values() and QuerySet.values_list() methods. When used on models with a JSONField, these methods are susceptible to SQL injection through column aliases if a crafted JSON object key is passed as an argument.

A security vulnerability has been discovered in certain versions of Django, affecting the password reset functionality. The PasswordResetForm class in django.contrib.auth.forms inadvertently allowed attackers to enumerate user email addresses by exploiting unhandled exceptions during the email sending process. This could be done by issuing password reset requests and observing the responses. Django has implemented a fix where these exceptions are now caught and logged using the django.contrib.auth logger, preventing potential information leakage through error responses.

Django 2.2.18, 3.0.12 and 3.1.6 include a fix for CVE-2021-3281: The django.utils.archive.extract method (used by "startapp --template" and "startproject --template") allows directory traversal via an archive with absolute paths or relative paths with dot segments.

Django 4.2.7, 4.1.13 and 3.2.23 include a fix for CVE-2023-46695: Potential denial of service vulnerability in UsernameField on Windows.
https://www.djangoproject.com/weblog/2023/nov/01/security-releases

Affected versions of Django are vulnerable to Denial-of-Service via django.utils.text.Truncator. The django.utils.text.Truncator chars() and words() methods (when used with html=True) are subject to a potential DoS (denial of service) attack via certain inputs with very long, potentially malformed HTML text. The chars() and words() methods are used to implement the truncatechars_html and truncatewords_html template filters, which are thus also vulnerable. NOTE: this issue exists because of an incomplete fix for CVE-2019-14232.

Affected versions of Django are affected by a username enumeration vulnerability caused by timing differences in the django.contrib.auth.backends.ModelBackend.authenticate() method. This method allowed remote attackers to enumerate users through a timing attack involving login requests for users with unusable passwords. The timing difference in the authentication process exposed whether a username was valid or not, potentially aiding attackers in gaining unauthorized access.

Django 2.2.28, 3.2.13 and 4.0.4 include a fix for CVE-2022-28347: A SQL injection issue was discovered in QuerySet.explain() in Django 2.2 before 2.2.28, 3.2 before 3.2.13, and 4.0 before 4.0.4. This occurs by passing a crafted dictionary (with dictionary expansion) as the **options argument, and placing the injection payload in an option name.
https://www.djangoproject.com/weblog/2022/apr/11/security-releases

Django 2.2.16, 3.0.10 and 3.1.1 include a fix for CVE-2020-24583: An issue was discovered in Django 2.2 before 2.2.16, 3.0 before 3.0.10, and 3.1 before 3.1.1 (when Python 3.7+ is used). FILE_UPLOAD_DIRECTORY_PERMISSIONS mode was not applied to intermediate-level directories created in the process of uploading files. It was also not applied to intermediate-level collected static directories when using the collectstatic management command.
#NOTE: This vulnerability affects only users of Python versions above 3.7.
https://www.djangoproject.com/weblog/2020/sep/01/security-releases

Django 3.2.17, 4.0.9 and 4.1.6 includes a fix for CVE-2023-23969: In Django 3.2 before 3.2.17, 4.0 before 4.0.9, and 4.1 before 4.1.6, the parsed values of Accept-Language headers are cached in order to avoid repetitive parsing. This leads to a potential denial-of-service vector via excessive memory usage if the raw value of Accept-Language headers is very large.
https://www.djangoproject.com/weblog/2023/feb/01/security-releases

Affected versions of the `django` package are vulnerable to Download of Code Without Integrity Check due to improper handling of user-supplied input in the HTTP FileResponse class. The vulnerability arises because the Content-Disposition header of a FileResponse can be set using a filename derived from user input without sufficient validation. An attacker can exploit this by crafting a request that causes a file with malicious content to be downloaded, potentially executing arbitrary code on the client system when the file is opened.

CVE-2025-64459: Affected versions of the Django package are vulnerable to SQL Injection due to improper input validation, allowing the internal _connector keyword argument to be accepted from untrusted dictionaries via expansion. The .filter(), .exclude(), and .get() methods on QuerySet, as well as the Q class, resolve **kwargs and will treat a supplied _connector value as the logical connector without constraining it to the expected set (AND/OR), permitting attacker-controlled tokens to influence SQL predicate construction.

Affected versions of the Django package are vulnerable to SQL Injection due to insufficient input sanitization in FilteredRelation column aliases. The FilteredRelation class fails to properly validate or escape column alias names when they are provided through dictionary expansion as keyword arguments to QuerySet.annotate() or QuerySet.alias() methods, allowing malicious SQL code to be injected directly into the generated database queries.

Django fixes potential SQL injection in ``FilteredRelation`` column aliases on PostgreSQL.

Affected versions of the sqlparse package are vulnerable to Denial of Service (DoS) due to missing hard limits on token grouping recursion depth and token processing when formatting very large SQL tuple lists. During sqlparse.format() processing, the sqlparse.engine.grouping._group_matching() and sqlparse.engine.grouping._group() functions can recurse and iterate over excessively large tlist.tokens without enforcing MAX_GROUPING_DEPTH or MAX_GROUPING_TOKENS, allowing grouping work to grow until it effectively hangs.

Affected versions of this package are vulnerable to Denial of Service (DoS) attacks due to Algorithmic Complexity. The SQL parser fails to enforce limits when processing deeply nested tuples and large token sequences, leading to excessive resource consumption through crafted SQL statements with extreme nesting depth or token counts.

**Note:** This issue is due to an incomplete fix for CVE-2024-4340.

Sqlparse 0.5.0 addresses a potential denial of service (DoS) vulnerability related to recursion errors in deeply nested SQL statements. To mitigate this issue, the update replaces recursion errors with a general SQLParseError, improving the resilience and stability of the parsing process.

Sqlparse 0.4.4 includes a fix for CVE-2023-30608: Parser contains a regular expression that is vulnerable to ReDOS (Regular Expression Denial of Service).
https://github.com/andialbrecht/sqlparse/security/advisories/GHSA-rrm6-wvj7-cwh2

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to redirect handling that drains connections by decompressing redirect response bodies without enforcing streaming read limits. The issue occurs when using urllib3’s streaming mode (for example, preload_content=False) while allowing redirects, because urllib3.response.HTTPResponse.drain_conn() would call HTTPResponse.read() in a way that decoded/decompressed the entire redirect response body even before any streaming reads were performed, effectively bypassing decompression-bomb safeguards.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to improper handling of highly compressed HTTP response bodies during streaming decompression. The urllib3.HTTPResponse methods stream(), read(), read1(), read_chunked(), and readinto() may fully decompress a minimal but highly compressed payload based on the Content-Encoding header into an internal buffer instead of limiting the decompressed output to the requested chunk size, causing excessive CPU usage and massive memory allocation on the client side.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to allowing an unbounded number of content-encoding decompression steps for HTTP responses. The HTTPResponse content decoding pipeline in urllib3 follows the Content-Encoding header and applies each advertised compression algorithm in sequence without enforcing a maximum chain length or effective output size, so a malicious peer can send a response with a very long encoding chain that triggers excessive CPU use and massive memory allocation during decompression.

Urllib3's ProxyManager ensures that the Proxy-Authorization header is correctly directed only to configured proxies. However, when HTTP requests bypass urllib3's proxy support, there's a risk of inadvertently setting the Proxy-Authorization header, which remains ineffective without a forwarding or tunneling proxy. Urllib3 does not recognize this header as carrying authentication data, failing to remove it during cross-origin redirects. While this scenario is uncommon and poses low risk to most users, urllib3 now proactively removes the Proxy-Authorization header during cross-origin redirects as a precautionary measure. Users are advised to utilize urllib3's proxy support or disable automatic redirects to handle the Proxy-Authorization header securely. Despite these precautions, urllib3 defaults to stripping the header to safeguard users who may inadvertently misconfigure requests.

Urllib3 1.26.17 and 2.0.5 include a fix for CVE-2023-43804: Urllib3 doesn't treat the 'Cookie' HTTP header special or provide any helpers for managing cookies over HTTP, that is the responsibility of the user. However, it is possible for a user to specify a 'Cookie' header and unknowingly leak information via HTTP redirects to a different origin if that user doesn't disable redirects explicitly.
https://github.com/urllib3/urllib3/security/advisories/GHSA-v845-jxx5-vc9f

Urllib3 1.26.5 includes a fix for CVE-2021-33503: When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking, causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redirect.
https://github.com/advisories/GHSA-q2q7-5pp4-w6pg

The _encode_invalid_chars function in util/url.py in the urllib3 library 1.25.2 through 1.25.7 for Python allows a denial of service (CPU consumption) because of an inefficient algorithm. The percent_encodings array contains all matches of percent encodings. It is not deduplicated. For a URL of length N, the size of percent_encodings may be up to O(N). The next step (normalize existing percent-encoded bytes) also takes up to O(N) for each step, so the total time is O(N^2). If percent_encodings were deduplicated, the time to compute _encode_invalid_chars would be O(kN), where k is at most 484 ((10+6*2)^2). See: CVE-2020-7212.

Affected versions of urllib3 are vulnerable to an HTTP redirect handling vulnerability that fails to remove the HTTP request body when a POST changes to a GET via 301, 302, or 303 responses. This flaw can expose sensitive request data if the origin service is compromised and redirects to a malicious endpoint, though exploitability is low when no sensitive data is used. The vulnerability affects automatic redirect behavior. It is fixed in versions 1.26.18 and 2.0.7; update or disable redirects using redirects=False.
This vulnerability is specific to Python's urllib3 library.

urllib3 is a user-friendly HTTP client library for Python. Prior to 2.5.0, it is possible to disable redirects for all requests by instantiating a PoolManager and specifying retries in a way that disable redirects. By default, requests and botocore users are not affected. An application attempting to mitigate SSRF or open redirect vulnerabilities by disabling redirects at the PoolManager level will remain vulnerable. This issue has been patched in version 2.5.0.

Urllib3 1.25.9 includes a fix for CVE-2020-26137: Urllib3 before 1.25.9 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserting CR and LF control characters in the first argument of putrequest(). NOTE: this is similar to CVE-2020-26116.
https://github.com/python/cpython/issues/83784
https://github.com/urllib3/urllib3/pull/1800

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to redirect handling that drains connections by decompressing redirect response bodies without enforcing streaming read limits. The issue occurs when using urllib3’s streaming mode (for example, preload_content=False) while allowing redirects, because urllib3.response.HTTPResponse.drain_conn() would call HTTPResponse.read() in a way that decoded/decompressed the entire redirect response body even before any streaming reads were performed, effectively bypassing decompression-bomb safeguards.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to improper handling of highly compressed HTTP response bodies during streaming decompression. The urllib3.HTTPResponse methods stream(), read(), read1(), read_chunked(), and readinto() may fully decompress a minimal but highly compressed payload based on the Content-Encoding header into an internal buffer instead of limiting the decompressed output to the requested chunk size, causing excessive CPU usage and massive memory allocation on the client side.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to allowing an unbounded number of content-encoding decompression steps for HTTP responses. The HTTPResponse content decoding pipeline in urllib3 follows the Content-Encoding header and applies each advertised compression algorithm in sequence without enforcing a maximum chain length or effective output size, so a malicious peer can send a response with a very long encoding chain that triggers excessive CPU use and massive memory allocation during decompression.

Urllib3's ProxyManager ensures that the Proxy-Authorization header is correctly directed only to configured proxies. However, when HTTP requests bypass urllib3's proxy support, there's a risk of inadvertently setting the Proxy-Authorization header, which remains ineffective without a forwarding or tunneling proxy. Urllib3 does not recognize this header as carrying authentication data, failing to remove it during cross-origin redirects. While this scenario is uncommon and poses low risk to most users, urllib3 now proactively removes the Proxy-Authorization header during cross-origin redirects as a precautionary measure. Users are advised to utilize urllib3's proxy support or disable automatic redirects to handle the Proxy-Authorization header securely. Despite these precautions, urllib3 defaults to stripping the header to safeguard users who may inadvertently misconfigure requests.

Urllib3 1.26.17 and 2.0.5 include a fix for CVE-2023-43804: Urllib3 doesn't treat the 'Cookie' HTTP header special or provide any helpers for managing cookies over HTTP, that is the responsibility of the user. However, it is possible for a user to specify a 'Cookie' header and unknowingly leak information via HTTP redirects to a different origin if that user doesn't disable redirects explicitly.
https://github.com/urllib3/urllib3/security/advisories/GHSA-v845-jxx5-vc9f

Urllib3 1.26.5 includes a fix for CVE-2021-33503: When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking, causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redirect.
https://github.com/advisories/GHSA-q2q7-5pp4-w6pg

The _encode_invalid_chars function in util/url.py in the urllib3 library 1.25.2 through 1.25.7 for Python allows a denial of service (CPU consumption) because of an inefficient algorithm. The percent_encodings array contains all matches of percent encodings. It is not deduplicated. For a URL of length N, the size of percent_encodings may be up to O(N). The next step (normalize existing percent-encoded bytes) also takes up to O(N) for each step, so the total time is O(N^2). If percent_encodings were deduplicated, the time to compute _encode_invalid_chars would be O(kN), where k is at most 484 ((10+6*2)^2). See: CVE-2020-7212.

Affected versions of urllib3 are vulnerable to an HTTP redirect handling vulnerability that fails to remove the HTTP request body when a POST changes to a GET via 301, 302, or 303 responses. This flaw can expose sensitive request data if the origin service is compromised and redirects to a malicious endpoint, though exploitability is low when no sensitive data is used. The vulnerability affects automatic redirect behavior. It is fixed in versions 1.26.18 and 2.0.7; update or disable redirects using redirects=False.
This vulnerability is specific to Python's urllib3 library.

urllib3 is a user-friendly HTTP client library for Python. Prior to 2.5.0, it is possible to disable redirects for all requests by instantiating a PoolManager and specifying retries in a way that disable redirects. By default, requests and botocore users are not affected. An application attempting to mitigate SSRF or open redirect vulnerabilities by disabling redirects at the PoolManager level will remain vulnerable. This issue has been patched in version 2.5.0.

Urllib3 1.25.9 includes a fix for CVE-2020-26137: Urllib3 before 1.25.9 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserting CR and LF control characters in the first argument of putrequest(). NOTE: this is similar to CVE-2020-26116.
https://github.com/python/cpython/issues/83784
https://github.com/urllib3/urllib3/pull/1800

Affected versions of the gunicorn package are vulnerable to HTTP Request/Response Smuggling due to improper validation of the Transfer-Encoding header that enables a TE.CL desynchronisation condition. Gunicorn’s HTTP parser does not consistently enforce RFC semantics when parsing conflicting or unsupported request framing—such as messages containing both Transfer-Encoding and Content-Length—so the backend may fall back to Content-Length while an intermediary treats the message as chunked.

Gunicorn 20.0.1 fixes chunked encoding support to prevent http request smuggling attacks.
https://github.com/benoitc/gunicorn/issues/2176
https://github.com/p4k03n4t0r/http-request-smuggling#request-smuggling-using-mitmproxy-and-gunicorn

Gunicorn fails to properly validate Transfer-Encoding headers, leading to HTTP Request Smuggling (HRS) vulnerabilities. By crafting requests with conflicting Transfer-Encoding headers, attackers can bypass security restrictions and access restricted endpoints. This issue is due to Gunicorn's handling of Transfer-Encoding headers, where it incorrectly processes requests with multiple, conflicting Transfer-Encoding headers, treating them as chunked regardless of the final encoding specified. This vulnerability allows for a range of attacks including cache poisoning, session manipulation, and data exposure.

Certifi 2022.12.07 includes a fix for CVE-2022-23491: Certifi 2022.12.07 removes root certificates from "TrustCor" from the root store. These are in the process of being removed from Mozilla's trust store. TrustCor's root certificates are being removed pursuant to an investigation prompted by media reporting that TrustCor's ownership also operated a business that produced spyware. Conclusions of Mozilla's investigation can be found in the linked google group discussion.

Certifi 2023.07.22 includes a fix for CVE-2023-37920: Certifi prior to version 2023.07.22 recognizes "e-Tugra" root certificates. e-Tugra's root certificates were subject to an investigation prompted by reporting of security issues in their systems. Certifi 2023.07.22 removes root certificates from "e-Tugra" from the root store.
https://github.com/certifi/python-certifi/security/advisories/GHSA-xqr8-7jwr-rhp7

Certifi 2022.12.07 includes a fix for CVE-2022-23491: Certifi 2022.12.07 removes root certificates from "TrustCor" from the root store. These are in the process of being removed from Mozilla's trust store. TrustCor's root certificates are being removed pursuant to an investigation prompted by media reporting that TrustCor's ownership also operated a business that produced spyware. Conclusions of Mozilla's investigation can be found in the linked google group discussion.

Certifi 2023.07.22 includes a fix for CVE-2023-37920: Certifi prior to version 2023.07.22 recognizes "e-Tugra" root certificates. e-Tugra's root certificates were subject to an investigation prompted by reporting of security issues in their systems. Certifi 2023.07.22 removes root certificates from "e-Tugra" from the root store.
https://github.com/certifi/python-certifi/security/advisories/GHSA-xqr8-7jwr-rhp7

Affected versions of Sentry's Python SDK are vulnerable to unintentional exposure of environment variables to subprocesses despite the env={} setting. In Python's 'subprocess' calls, all environment variables are passed to subprocesses by default. However, if you specifically do not want them to be passed to subprocesses, you may use 'env' argument in 'subprocess' calls. Due to the bug in Sentry SDK, with the Stdlib integration enabled (which is enabled by default), this expectation is not fulfilled, and all environment variables are being passed to subprocesses instead. 
As a workaround, and if passing environment variables to child processes poses a security risk for you, you can disable all default integrations.

Sentry-sdk 1.14.0 includes a fix for CVE-2023-28117: When using the Django integration of versions prior to 1.14.0 of the Sentry SDK in a specific configuration it is possible to leak sensitive cookies values, including the session cookie to Sentry. These sensitive cookies could then be used by someone with access to your Sentry issues to impersonate or escalate their privileges within your application. In order for these sensitive values to be leaked, the Sentry SDK configuration must have 'sendDefaultPII' set to 'True'; one must use a custom name for either 'SESSION_COOKIE_NAME' or 'CSRF_COOKIE_NAME' in one's Django settings; and one must not be configured in one's organization or project settings to use Sentry's data scrubbing features to account for the custom cookie names. As of version 1.14.0, the Django integration of the 'sentry-sdk' will detect the custom cookie names based on one's Django settings and will remove the values from the payload before sending the data to Sentry. As a workaround, use the SDK's filtering mechanism to remove the cookies from the payload that is sent to Sentry. For error events, this can be done with the 'before_send' callback method and for performance related events (transactions) one can use the 'before_send_transaction' callback method. Those who want to handle filtering of these values on the server-side can also use Sentry's advanced data scrubbing feature to account for the custom cookie names. Look for the '$http.cookies', '$http.headers', '$request.cookies', or '$request.headers' fields to target with a scrubbing rule.
https://github.com/getsentry/sentry-python/security/advisories/GHSA-29pr-6jr8-q5jm

Sentry-sdk 1.4.1 includes a fix for a Race Condition vulnerability.
https://github.com/getsentry/sentry-python/pull/1203

A SQL Injection issue in the SQL Panel in Jazzband Django Debug Toolbar before 1.11.1, 2.x before 2.2.1, and 3.x before 3.2.1 allows attackers to execute SQL statements by changing the raw_sql input field of the SQL explain, analyze, or select form. See CVE-2021-30459.

** DISPUTED ** Py throughout 1.11.0 allows remote attackers to conduct a ReDoS (Regular expression Denial of Service) attack via a Subversion repository with crafted info data because the InfoSvnCommand argument is mishandled.
https://github.com/pytest-dev/py/issues/287

Py 1.10.0 includes a fix for CVE-2020-29651: A denial of service via regular expression in the py.path.svnwc component of py (aka python-py) through 1.9.0 could be used by attackers to cause a compute-time denial of service attack by supplying malicious input to the blame functionality.

Affected versions of Idna are vulnerable to Denial Of Service via the idna.encode(), where a specially crafted argument could lead to significant resource consumption. In version 3.7, this function has been updated to reject such inputs efficiently, minimizing resource use. A practical workaround involves enforcing a maximum domain name length of 253 characters before encoding, as the vulnerability is triggered by unusually large inputs that normal operations wouldn't encounter.

** DISPUTED ** Py throughout 1.11.0 allows remote attackers to conduct a ReDoS (Regular expression Denial of Service) attack via a Subversion repository with crafted info data because the InfoSvnCommand argument is mishandled.
https://github.com/pytest-dev/py/issues/287

Py 1.10.0 includes a fix for CVE-2020-29651: A denial of service via regular expression in the py.path.svnwc component of py (aka python-py) through 1.9.0 could be used by attackers to cause a compute-time denial of service attack by supplying malicious input to the blame functionality.

An issue was discovered in Django 2.2 before 2.2.13 and 3.0 before 3.0.7. Query parameters generated by the Django admin ForeignKeyRawIdWidget were not properly URL encoded, leading to a possibility of an XSS attack.

Affected versions of the Django package are vulnerable to SQL Injection due to improper handling of control characters in column aliases within FilteredRelation. The FilteredRelation class fails to properly sanitize column aliases containing control characters when used with QuerySet methods annotate(), aggregate(), extra(), values(), values_list(), and alias() via dictionary expansion (**kwargs).

Affected versions of the Django package are vulnerable to SQL Injection due to improper sanitization of band index parameters in PostGIS raster lookups. The raster lookup functionality in Django's GIS module fails to properly validate or escape untrusted data used as a band index when performing spatial queries against PostGIS databases.

Affected versions of Django are vulnerable to potential denial-of-service in intcomma template filter when used with very long strings.

A potential denial-of-service vulnerability has been identified in Django's urlize() and urlizetrunc() functions in django.utils.html. This vulnerability can be triggered by inputting huge strings containing a specific sequence of characters.

Django 3.2.14 and 4.0.6 include a fix for CVE-2022-34265: Potential SQL injection via Trunc(kind) and Extract(lookup_name) arguments.
https://www.djangoproject.com/weblog/2022/jul/04/security-releases

An issue was discovered in Django 2.2 before 2.2.13 and 3.0 before 3.0.7. In cases where a memcached backend does not perform key validation, passing malformed cache keys could result in a key collision, and potential data leakage.

Django 4.1.7, 4.0.10 and 3.2.18 include a fix for CVE-2023-24580: Potential denial-of-service vulnerability in file uploads.
https://www.djangoproject.com/weblog/2023/feb/14/security-releases

An issue was discovered in Django 2.2 before 2.2.16, 3.0 before 3.0.10, and 3.1 before 3.1.1 (when Python 3.7+ is used). The intermediate-level directories of the filesystem cache had the system's standard umask rather than 0o077.

Django versions 3.2.2, 3.1.10 and 2.2.22 include a fix for CVE-2021-32052: In Django 2.2 before 2.2.22, 3.1 before 3.1.10, and 3.2 before 3.2.2 (with Python 3.9.5+), URLValidator does not prohibit newlines and tabs (unless the URLField form field is used). If an application uses values with newlines in an HTTP response, header injection can occur. Django itself is unaffected because HttpResponse prohibits newlines in HTTP headers.
https://www.djangoproject.com/weblog/2021/may/06/security-releases

Affected versions of the Django package are vulnerable to Path Traversal due to improper validation of file paths in the django.contrib.admindocs module. The `TemplateDetailView` view allows staff members to verify the existence of arbitrary files by manipulating the file path. An attacker with staff privileges can exploit this vulnerability to check for the presence of files outside the template root directories, and if the `admindocs` templates are customized to display file contents, they can also access the contents of these files.

Django addresses a memory exhaustion issue in django.utils.numberformat.floatformat(). When floatformat receives a string representation of a number in scientific notation with a large exponent, it could lead to excessive memory consumption. To prevent this, decimals with more than 200 digits are now returned as-is.

Django 2.2.24, 3.1.12, and 3.2.4 include a fix for CVE-2021-33571: In Django 2.2 before 2.2.24, 3.x before 3.1.12, and 3.2 before 3.2.4, URLValidator, validate_ipv4_address, and validate_ipv46_address do not prohibit leading zero characters in octal literals. This may allow a bypass of access control that is based on IP addresses. (validate_ipv4_address and validate_ipv46_address are unaffected with Python 3.9.5+).
https://www.djangoproject.com/weblog/2021/jun/02/security-releases

Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to inefficient string concatenation when processing duplicate HTTP headers in ASGI mode. The ASGIRequest class combines repeated headers using repeated string concatenation, resulting in super-linear (quadratic) time complexity when processing requests with many duplicate headers.

Affected versions of the Django package are vulnerable to SQL Injection due to improper handling of column aliases containing periods in QuerySet.order_by() when combined with FilteredRelation. The QuerySet.order_by() method fails to properly sanitize column aliases that contain periods when the same alias is used in FilteredRelation via dictionary expansion. 
https://github.com/django/django/commit/90f5b10784ba5bf369caed87640e2b4394ea3314

Django 2.2.21, 3.1.9 and 3.2.1 include a fix for CVE-2021-31542: MultiPartParser, UploadedFile, and FieldFile allowed directory traversal via uploaded files with suitably crafted file names.
https://www.djangoproject.com/weblog/2021/may/04/security-releases

An issue was discovered in Django 4.2 before 4.2.21, 5.1 before 5.1.9, and 5.2 before 5.2.1. The django.utils.html.strip_tags() function is vulnerable to a potential denial-of-service (slow performance) when processing inputs containing large sequences of incomplete HTML tags. The template filter striptags is also vulnerable, because it is built on top of strip_tags().

In Django 3.2 before 3.2.16, 4.0 before 4.0.8, and 4.1 before 4.1.2, internationalized URLs were subject to a potential denial of service attack via the locale parameter, which is treated as a regular expression.

Affected versions of Django are vulnerable to potential Denial of Service via certain inputs with a very large number of Unicode characters in django.utils.encoding.uri_to_iri().

Django 1.11.29, 2.2.11 and 3.0.4 includes a fix for CVE-2020-9402: Django 1.11 before 1.11.29, 2.2 before 2.2.11, and 3.0 before 3.0.4 allows SQL Injection if untrusted data is used as a tolerance parameter in GIS functions and aggregates on Oracle. By passing a suitably crafted tolerance to GIS functions and aggregates on Oracle, it was possible to break escaping and inject malicious SQL.
https://www.djangoproject.com/weblog/2020/mar/04/security-releases

Django affected versions are vulnerable to a potential SQL injection in the HasKey(lhs, rhs) lookup on Oracle databases. The vulnerability arises when untrusted data is directly used as the lhs value in the django.db.models.fields.json.HasKey lookup. However, applications using the jsonfield.has_key lookup with the __ syntax remain unaffected by this issue.

Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to quadratic time complexity during HTML parsing in text truncation methods. The django.utils.text.Truncator.chars() and Truncator.words() methods (with html=True), as well as the truncatechars_html and truncatewords_html template filters, exhibit quadratic time complexity when processing inputs containing a large number of unmatched HTML end tags.

Django versions 2.2.25, 3.1.14 and 3.2.10 include a fix for CVE-2021-44420: In Django 2.2 before 2.2.25, 3.1 before 3.1.14, and 3.2 before 3.2.10, HTTP requests for URLs with trailing newlines could bypass upstream access control based on URL paths.
https://www.djangoproject.com/weblog/2021/dec/07/security-releases/

Django 2.1.15 and 2.2.8 includes a fix for CVE-2019-19118: A Django model admin displaying inline related models, where the user has view-only permissions to a parent model but edit permissions to the inline model, would be presented with an editing UI, allowing POST requests, for updating the inline model. Directly editing the view-only parent model was not possible, but the parent model's save() method was called, triggering potential side effects, and causing pre and post-save signal handlers to be invoked. To resolve this, the Django admin is adjusted to require edit permissions on the parent model in order for inline models to be editable.

Django 1.11.27, 2.2.9 and 3.0.1 include a fix for CVE-2019-19844: Account takeover. A suitably crafted email address (that is equal to an existing user's email address after case transformation of Unicode characters) would allow an attacker to be sent a password reset token for the matched user account. One mitigation in the new releases is to send password reset tokens only to the registered user email address.

Django has a potential denial-of-service vulnerability in django.utils.html.urlize() and AdminURLFieldWidget. The urlize and urlizetrunc functions, along with AdminURLFieldWidget, are vulnerable to denial-of-service attacks when handling inputs with a very large number of Unicode characters.

Affected versions of Django are potentially vulnerable to denial-of-service via the get_supported_language_variant() method. This method was susceptible to a denial-of-service attack when used with very long strings containing specific characters. Exploiting this vulnerability could cause significant delays or crashes in the affected application, potentially leading to service disruption.

Django versions 2.2.19, 3.0.13 and 3.1.7 include a fix for CVE-2021-23336: Web cache poisoning via 'django.utils.http.limited_parse_qsl()'. Django contains a copy of 'urllib.parse.parse_qsl' which was added to backport some security fixes. A further security fix has been issued recently such that 'parse_qsl(' no longer allows using ';' as a query parameter separator by default.

Django 4.2.1, 4.1.9 and 3.2.19 include a fix for CVE-2023-31047: In Django 3.2 before 3.2.19, 4.x before 4.1.9, and 4.2 before 4.2.1, it was possible to bypass validation when using one form field to upload multiple files. This multiple upload has never been supported by forms.FileField or forms.ImageField (only the last uploaded file was validated). However, Django's "Uploading multiple files" documentation suggested otherwise.
https://www.djangoproject.com/weblog/2023/may/03/security-releases

Affected versions of Django are vulnerable to potential regular expression denial-of-service (REDoS). django.utils.text.Truncator.words() method (with html=True) and truncatewords_html template filter were subject to a potential regular expression denial-of-service attack using a suitably crafted string (follow up to CVE-2019-14232 and CVE-2023-43665).

Affected versions of Django are vulnerable to a potential ReDoS (regular expression denial of service) in EmailValidator and URLValidator via a very large number of domain name labels of emails and URLs.

Django 2.2.27, 3.2.12 and 4.0.2 include a fix for CVE-2022-23833: Denial-of-service possibility in file uploads.
https://www.djangoproject.com/weblog/2022/feb/01/security-releases

Django 2.2.28, 3.2.13 and 4.0.4 include a fix for CVE-2022-28346: An issue was discovered in Django 2.2 before 2.2.28, 3.2 before 3.2.13, and 4.0 before 4.0.4. QuerySet.annotate(), aggregate(), and extra() methods are subject to SQL injection in column aliases via a crafted dictionary (with dictionary expansion) as the passed **kwargs.
https://www.djangoproject.com/weblog/2022/apr/11/security-releases

In Django 2.2 before 2.2.20, 3.0 before 3.0.14, and 3.1 before 3.1.8, MultiPartParser allowed directory traversal via uploaded files with suitably crafted file names. Built-in upload handlers were not affected by this vulnerability.

CVE-2025-64458: Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to slow Unicode NFKC normalization on Windows being applied to untrusted inputs. The django.contrib.auth.views.LoginView and django.contrib.auth.views.LogoutView, and django.views.i18n.set_language normalize user-controlled strings using Python’s NFKC algorithm, which is unusually slow on Windows for huge Unicode sequences and can be triggered to consume excessive CPU.

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45452: Storage.save in Django 2.2 before 2.2.26, 3.2 before 3.2.11, and 4.0 before 4.0.1 allows directory traversal if crafted filenames are directly passed to it.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases/

Affected versions of Django are vulnerable to a potential denial-of-service (DoS) attack in the `django.utils.html.strip_tags()` method. The vulnerability occurs when the `strip_tags()` method or the `striptags` template filter processes inputs containing large sequences of nested, incomplete HTML entities.

Affected versions of the Django package are vulnerable to Information Disclosure (Timing Attack) due to non-constant-time comparison in the mod_wsgi authentication handler. The django.contrib.auth.handlers.modwsgi.check_password() function does not perform user existence checks in constant time, allowing response timing differences to reveal whether usernames exist.

The {% debug %} template tag in Django 2.2 before 2.2.27, 3.2 before 3.2.12, and 4.0 before 4.0.2 does not properly encode the current context. This may lead to XSS.

Django fixes a potential denial-of-service vulnerability in XML ``Deserializer``.

An issue was discovered in Django 5.2 before 5.2.3, 5.1 before 5.1.11, and 4.2 before 4.2.23. Internal HTTP response logging does not escape request.path, which allows remote attackers to potentially manipulate log output via crafted URLs. This may lead to log injection or forgery when logs are viewed in terminals or processed by external systems.

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45116: An issue was discovered in Django 2.2 before 2.2.26, 3.2 before 3.2.11, and 4.0 before 4.0.1. Due to leveraging the Django Template Language's variable resolution logic, the dictsort template filter was potentially vulnerable to information disclosure, or an unintended method call, if passed a suitably crafted key.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45115: UserAttributeSimilarityValidator incurred significant overhead in evaluating a submitted password that was artificially large in relation to the comparison values. In a situation where access to user registration was unrestricted, this provided a potential vector for a denial-of-service attack.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases/

Affected versions of Django are affected by a potential denial-of-service vulnerability in the django.utils.html.urlize() function. The urlize and urlizetrunc template filters were susceptible to a denial-of-service attack via certain inputs containing many brackets. An attacker could exploit this vulnerability to cause significant delays or crashes in the affected application.

Affected versions of Django are affected by a directory-traversal vulnerability in the Storage.save() method. Derived classes of the django.core.files.storage.Storage base class that overrides the generate_filename() method without replicating the file path validations existing in the parent class could allow for directory traversal via certain inputs when calling save(). This could enable an attacker to manipulate file paths and access unintended directories.

Django 1.11.28, 2.2.10 and 3.0.3 include a fix for CVE-2020-7471: SQL Injection if untrusted data is used as a StringAgg delimiter (e.g., in Django applications that offer downloads of data as a series of rows with a user-specified column delimiter). By passing a suitably crafted delimiter to a contrib.postgres.aggregates.StringAgg instance, it was possible to break escaping and inject malicious SQL.

Affected versions of Django has a potential SQL injection vulnerability in the QuerySet.values() and QuerySet.values_list() methods. When used on models with a JSONField, these methods are susceptible to SQL injection through column aliases if a crafted JSON object key is passed as an argument.

A security vulnerability has been discovered in certain versions of Django, affecting the password reset functionality. The PasswordResetForm class in django.contrib.auth.forms inadvertently allowed attackers to enumerate user email addresses by exploiting unhandled exceptions during the email sending process. This could be done by issuing password reset requests and observing the responses. Django has implemented a fix where these exceptions are now caught and logged using the django.contrib.auth logger, preventing potential information leakage through error responses.

Django 2.2.18, 3.0.12 and 3.1.6 include a fix for CVE-2021-3281: The django.utils.archive.extract method (used by "startapp --template" and "startproject --template") allows directory traversal via an archive with absolute paths or relative paths with dot segments.

Django 4.2.7, 4.1.13 and 3.2.23 include a fix for CVE-2023-46695: Potential denial of service vulnerability in UsernameField on Windows.
https://www.djangoproject.com/weblog/2023/nov/01/security-releases

Affected versions of Django are vulnerable to Denial-of-Service via django.utils.text.Truncator. The django.utils.text.Truncator chars() and words() methods (when used with html=True) are subject to a potential DoS (denial of service) attack via certain inputs with very long, potentially malformed HTML text. The chars() and words() methods are used to implement the truncatechars_html and truncatewords_html template filters, which are thus also vulnerable. NOTE: this issue exists because of an incomplete fix for CVE-2019-14232.

Affected versions of Django are affected by a username enumeration vulnerability caused by timing differences in the django.contrib.auth.backends.ModelBackend.authenticate() method. This method allowed remote attackers to enumerate users through a timing attack involving login requests for users with unusable passwords. The timing difference in the authentication process exposed whether a username was valid or not, potentially aiding attackers in gaining unauthorized access.

Django 2.2.28, 3.2.13 and 4.0.4 include a fix for CVE-2022-28347: A SQL injection issue was discovered in QuerySet.explain() in Django 2.2 before 2.2.28, 3.2 before 3.2.13, and 4.0 before 4.0.4. This occurs by passing a crafted dictionary (with dictionary expansion) as the **options argument, and placing the injection payload in an option name.
https://www.djangoproject.com/weblog/2022/apr/11/security-releases

Django 2.2.16, 3.0.10 and 3.1.1 include a fix for CVE-2020-24583: An issue was discovered in Django 2.2 before 2.2.16, 3.0 before 3.0.10, and 3.1 before 3.1.1 (when Python 3.7+ is used). FILE_UPLOAD_DIRECTORY_PERMISSIONS mode was not applied to intermediate-level directories created in the process of uploading files. It was also not applied to intermediate-level collected static directories when using the collectstatic management command.
#NOTE: This vulnerability affects only users of Python versions above 3.7.
https://www.djangoproject.com/weblog/2020/sep/01/security-releases

Django 3.2.17, 4.0.9 and 4.1.6 includes a fix for CVE-2023-23969: In Django 3.2 before 3.2.17, 4.0 before 4.0.9, and 4.1 before 4.1.6, the parsed values of Accept-Language headers are cached in order to avoid repetitive parsing. This leads to a potential denial-of-service vector via excessive memory usage if the raw value of Accept-Language headers is very large.
https://www.djangoproject.com/weblog/2023/feb/01/security-releases

Affected versions of the `django` package are vulnerable to Download of Code Without Integrity Check due to improper handling of user-supplied input in the HTTP FileResponse class. The vulnerability arises because the Content-Disposition header of a FileResponse can be set using a filename derived from user input without sufficient validation. An attacker can exploit this by crafting a request that causes a file with malicious content to be downloaded, potentially executing arbitrary code on the client system when the file is opened.

CVE-2025-64459: Affected versions of the Django package are vulnerable to SQL Injection due to improper input validation, allowing the internal _connector keyword argument to be accepted from untrusted dictionaries via expansion. The .filter(), .exclude(), and .get() methods on QuerySet, as well as the Q class, resolve **kwargs and will treat a supplied _connector value as the logical connector without constraining it to the expected set (AND/OR), permitting attacker-controlled tokens to influence SQL predicate construction.

Affected versions of the Django package are vulnerable to SQL Injection due to insufficient input sanitization in FilteredRelation column aliases. The FilteredRelation class fails to properly validate or escape column alias names when they are provided through dictionary expansion as keyword arguments to QuerySet.annotate() or QuerySet.alias() methods, allowing malicious SQL code to be injected directly into the generated database queries.

Django fixes potential SQL injection in ``FilteredRelation`` column aliases on PostgreSQL.

Affected versions of the sqlparse package are vulnerable to Denial of Service (DoS) due to missing hard limits on token grouping recursion depth and token processing when formatting very large SQL tuple lists. During sqlparse.format() processing, the sqlparse.engine.grouping._group_matching() and sqlparse.engine.grouping._group() functions can recurse and iterate over excessively large tlist.tokens without enforcing MAX_GROUPING_DEPTH or MAX_GROUPING_TOKENS, allowing grouping work to grow until it effectively hangs.

Affected versions of this package are vulnerable to Denial of Service (DoS) attacks due to Algorithmic Complexity. The SQL parser fails to enforce limits when processing deeply nested tuples and large token sequences, leading to excessive resource consumption through crafted SQL statements with extreme nesting depth or token counts.

**Note:** This issue is due to an incomplete fix for CVE-2024-4340.

Sqlparse 0.5.0 addresses a potential denial of service (DoS) vulnerability related to recursion errors in deeply nested SQL statements. To mitigate this issue, the update replaces recursion errors with a general SQLParseError, improving the resilience and stability of the parsing process.

Sqlparse 0.4.4 includes a fix for CVE-2023-30608: Parser contains a regular expression that is vulnerable to ReDOS (Regular Expression Denial of Service).
https://github.com/andialbrecht/sqlparse/security/advisories/GHSA-rrm6-wvj7-cwh2

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to redirect handling that drains connections by decompressing redirect response bodies without enforcing streaming read limits. The issue occurs when using urllib3’s streaming mode (for example, preload_content=False) while allowing redirects, because urllib3.response.HTTPResponse.drain_conn() would call HTTPResponse.read() in a way that decoded/decompressed the entire redirect response body even before any streaming reads were performed, effectively bypassing decompression-bomb safeguards.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to improper handling of highly compressed HTTP response bodies during streaming decompression. The urllib3.HTTPResponse methods stream(), read(), read1(), read_chunked(), and readinto() may fully decompress a minimal but highly compressed payload based on the Content-Encoding header into an internal buffer instead of limiting the decompressed output to the requested chunk size, causing excessive CPU usage and massive memory allocation on the client side.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to allowing an unbounded number of content-encoding decompression steps for HTTP responses. The HTTPResponse content decoding pipeline in urllib3 follows the Content-Encoding header and applies each advertised compression algorithm in sequence without enforcing a maximum chain length or effective output size, so a malicious peer can send a response with a very long encoding chain that triggers excessive CPU use and massive memory allocation during decompression.

Urllib3's ProxyManager ensures that the Proxy-Authorization header is correctly directed only to configured proxies. However, when HTTP requests bypass urllib3's proxy support, there's a risk of inadvertently setting the Proxy-Authorization header, which remains ineffective without a forwarding or tunneling proxy. Urllib3 does not recognize this header as carrying authentication data, failing to remove it during cross-origin redirects. While this scenario is uncommon and poses low risk to most users, urllib3 now proactively removes the Proxy-Authorization header during cross-origin redirects as a precautionary measure. Users are advised to utilize urllib3's proxy support or disable automatic redirects to handle the Proxy-Authorization header securely. Despite these precautions, urllib3 defaults to stripping the header to safeguard users who may inadvertently misconfigure requests.

Urllib3 1.26.17 and 2.0.5 include a fix for CVE-2023-43804: Urllib3 doesn't treat the 'Cookie' HTTP header special or provide any helpers for managing cookies over HTTP, that is the responsibility of the user. However, it is possible for a user to specify a 'Cookie' header and unknowingly leak information via HTTP redirects to a different origin if that user doesn't disable redirects explicitly.
https://github.com/urllib3/urllib3/security/advisories/GHSA-v845-jxx5-vc9f

Urllib3 1.26.5 includes a fix for CVE-2021-33503: When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking, causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redirect.
https://github.com/advisories/GHSA-q2q7-5pp4-w6pg

The _encode_invalid_chars function in util/url.py in the urllib3 library 1.25.2 through 1.25.7 for Python allows a denial of service (CPU consumption) because of an inefficient algorithm. The percent_encodings array contains all matches of percent encodings. It is not deduplicated. For a URL of length N, the size of percent_encodings may be up to O(N). The next step (normalize existing percent-encoded bytes) also takes up to O(N) for each step, so the total time is O(N^2). If percent_encodings were deduplicated, the time to compute _encode_invalid_chars would be O(kN), where k is at most 484 ((10+6*2)^2). See: CVE-2020-7212.

Affected versions of urllib3 are vulnerable to an HTTP redirect handling vulnerability that fails to remove the HTTP request body when a POST changes to a GET via 301, 302, or 303 responses. This flaw can expose sensitive request data if the origin service is compromised and redirects to a malicious endpoint, though exploitability is low when no sensitive data is used. The vulnerability affects automatic redirect behavior. It is fixed in versions 1.26.18 and 2.0.7; update or disable redirects using redirects=False.
This vulnerability is specific to Python's urllib3 library.

urllib3 is a user-friendly HTTP client library for Python. Prior to 2.5.0, it is possible to disable redirects for all requests by instantiating a PoolManager and specifying retries in a way that disable redirects. By default, requests and botocore users are not affected. An application attempting to mitigate SSRF or open redirect vulnerabilities by disabling redirects at the PoolManager level will remain vulnerable. This issue has been patched in version 2.5.0.

Urllib3 1.25.9 includes a fix for CVE-2020-26137: Urllib3 before 1.25.9 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserting CR and LF control characters in the first argument of putrequest(). NOTE: this is similar to CVE-2020-26116.
https://github.com/python/cpython/issues/83784
https://github.com/urllib3/urllib3/pull/1800

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to redirect handling that drains connections by decompressing redirect response bodies without enforcing streaming read limits. The issue occurs when using urllib3’s streaming mode (for example, preload_content=False) while allowing redirects, because urllib3.response.HTTPResponse.drain_conn() would call HTTPResponse.read() in a way that decoded/decompressed the entire redirect response body even before any streaming reads were performed, effectively bypassing decompression-bomb safeguards.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to improper handling of highly compressed HTTP response bodies during streaming decompression. The urllib3.HTTPResponse methods stream(), read(), read1(), read_chunked(), and readinto() may fully decompress a minimal but highly compressed payload based on the Content-Encoding header into an internal buffer instead of limiting the decompressed output to the requested chunk size, causing excessive CPU usage and massive memory allocation on the client side.

Affected versions of the urllib3 package are vulnerable to Denial of Service (DoS) due to allowing an unbounded number of content-encoding decompression steps for HTTP responses. The HTTPResponse content decoding pipeline in urllib3 follows the Content-Encoding header and applies each advertised compression algorithm in sequence without enforcing a maximum chain length or effective output size, so a malicious peer can send a response with a very long encoding chain that triggers excessive CPU use and massive memory allocation during decompression.

Urllib3's ProxyManager ensures that the Proxy-Authorization header is correctly directed only to configured proxies. However, when HTTP requests bypass urllib3's proxy support, there's a risk of inadvertently setting the Proxy-Authorization header, which remains ineffective without a forwarding or tunneling proxy. Urllib3 does not recognize this header as carrying authentication data, failing to remove it during cross-origin redirects. While this scenario is uncommon and poses low risk to most users, urllib3 now proactively removes the Proxy-Authorization header during cross-origin redirects as a precautionary measure. Users are advised to utilize urllib3's proxy support or disable automatic redirects to handle the Proxy-Authorization header securely. Despite these precautions, urllib3 defaults to stripping the header to safeguard users who may inadvertently misconfigure requests.

Urllib3 1.26.17 and 2.0.5 include a fix for CVE-2023-43804: Urllib3 doesn't treat the 'Cookie' HTTP header special or provide any helpers for managing cookies over HTTP, that is the responsibility of the user. However, it is possible for a user to specify a 'Cookie' header and unknowingly leak information via HTTP redirects to a different origin if that user doesn't disable redirects explicitly.
https://github.com/urllib3/urllib3/security/advisories/GHSA-v845-jxx5-vc9f

Urllib3 1.26.5 includes a fix for CVE-2021-33503: When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking, causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redirect.
https://github.com/advisories/GHSA-q2q7-5pp4-w6pg

The _encode_invalid_chars function in util/url.py in the urllib3 library 1.25.2 through 1.25.7 for Python allows a denial of service (CPU consumption) because of an inefficient algorithm. The percent_encodings array contains all matches of percent encodings. It is not deduplicated. For a URL of length N, the size of percent_encodings may be up to O(N). The next step (normalize existing percent-encoded bytes) also takes up to O(N) for each step, so the total time is O(N^2). If percent_encodings were deduplicated, the time to compute _encode_invalid_chars would be O(kN), where k is at most 484 ((10+6*2)^2). See: CVE-2020-7212.

Affected versions of urllib3 are vulnerable to an HTTP redirect handling vulnerability that fails to remove the HTTP request body when a POST changes to a GET via 301, 302, or 303 responses. This flaw can expose sensitive request data if the origin service is compromised and redirects to a malicious endpoint, though exploitability is low when no sensitive data is used. The vulnerability affects automatic redirect behavior. It is fixed in versions 1.26.18 and 2.0.7; update or disable redirects using redirects=False.
This vulnerability is specific to Python's urllib3 library.

urllib3 is a user-friendly HTTP client library for Python. Prior to 2.5.0, it is possible to disable redirects for all requests by instantiating a PoolManager and specifying retries in a way that disable redirects. By default, requests and botocore users are not affected. An application attempting to mitigate SSRF or open redirect vulnerabilities by disabling redirects at the PoolManager level will remain vulnerable. This issue has been patched in version 2.5.0.

Urllib3 1.25.9 includes a fix for CVE-2020-26137: Urllib3 before 1.25.9 allows CRLF injection if the attacker controls the HTTP request method, as demonstrated by inserting CR and LF control characters in the first argument of putrequest(). NOTE: this is similar to CVE-2020-26116.
https://github.com/python/cpython/issues/83784
https://github.com/urllib3/urllib3/pull/1800

Affected versions of the gunicorn package are vulnerable to HTTP Request/Response Smuggling due to improper validation of the Transfer-Encoding header that enables a TE.CL desynchronisation condition. Gunicorn’s HTTP parser does not consistently enforce RFC semantics when parsing conflicting or unsupported request framing—such as messages containing both Transfer-Encoding and Content-Length—so the backend may fall back to Content-Length while an intermediary treats the message as chunked.

Gunicorn 20.0.1 fixes chunked encoding support to prevent http request smuggling attacks.
https://github.com/benoitc/gunicorn/issues/2176
https://github.com/p4k03n4t0r/http-request-smuggling#request-smuggling-using-mitmproxy-and-gunicorn

Gunicorn fails to properly validate Transfer-Encoding headers, leading to HTTP Request Smuggling (HRS) vulnerabilities. By crafting requests with conflicting Transfer-Encoding headers, attackers can bypass security restrictions and access restricted endpoints. This issue is due to Gunicorn's handling of Transfer-Encoding headers, where it incorrectly processes requests with multiple, conflicting Transfer-Encoding headers, treating them as chunked regardless of the final encoding specified. This vulnerability allows for a range of attacks including cache poisoning, session manipulation, and data exposure.

Requests is an HTTP library. Due to a URL parsing issue, Requests releases prior to 2.32.4 may leak .netrc credentials to third parties for specific maliciously-crafted URLs. Users should upgrade to version 2.32.4 to receive a fix. For older versions of Requests, use of the .netrc file can be disabled with `trust_env=False` on one's Requests Session.

Affected versions of Requests are vulnerable to proxy credential leakage. When redirected to an HTTPS endpoint, the Proxy-Authorization header is forwarded to the destination server due to the use of rebuild_proxies to reattach the header. This may allow a malicious actor to exfiltrate sensitive information.

Affected versions of the requests package are vulnerable to Insecure Temporary File reuse due to predictable temporary filename generation in extract_zipped_paths(). The requests.utils.extract_zipped_paths() utility extracts files from zip archives into the system temporary directory using a deterministic path, and if that file already exists, the function reuses it without validating that it is the expected extracted content.

Affected versions of Requests, when making requests through a Requests `Session`, if the first request is made with `verify=False` to disable cert verification, all subsequent requests to the same host will continue to ignore cert verification regardless of changes to the value of `verify`. This behavior will continue for the lifecycle of the connection in the connection pool. Requests 2.32.0 fixes the issue, but versions 2.32.0 and 2.32.1 were yanked due to conflicts with CVE-2024-35195 mitigation.

Certifi 2022.12.07 includes a fix for CVE-2022-23491: Certifi 2022.12.07 removes root certificates from "TrustCor" from the root store. These are in the process of being removed from Mozilla's trust store. TrustCor's root certificates are being removed pursuant to an investigation prompted by media reporting that TrustCor's ownership also operated a business that produced spyware. Conclusions of Mozilla's investigation can be found in the linked google group discussion.

Certifi 2023.07.22 includes a fix for CVE-2023-37920: Certifi prior to version 2023.07.22 recognizes "e-Tugra" root certificates. e-Tugra's root certificates were subject to an investigation prompted by reporting of security issues in their systems. Certifi 2023.07.22 removes root certificates from "e-Tugra" from the root store.
https://github.com/certifi/python-certifi/security/advisories/GHSA-xqr8-7jwr-rhp7

Certifi 2022.12.07 includes a fix for CVE-2022-23491: Certifi 2022.12.07 removes root certificates from "TrustCor" from the root store. These are in the process of being removed from Mozilla's trust store. TrustCor's root certificates are being removed pursuant to an investigation prompted by media reporting that TrustCor's ownership also operated a business that produced spyware. Conclusions of Mozilla's investigation can be found in the linked google group discussion.

Certifi 2023.07.22 includes a fix for CVE-2023-37920: Certifi prior to version 2023.07.22 recognizes "e-Tugra" root certificates. e-Tugra's root certificates were subject to an investigation prompted by reporting of security issues in their systems. Certifi 2023.07.22 removes root certificates from "e-Tugra" from the root store.
https://github.com/certifi/python-certifi/security/advisories/GHSA-xqr8-7jwr-rhp7

Affected versions of Sentry's Python SDK are vulnerable to unintentional exposure of environment variables to subprocesses despite the env={} setting. In Python's 'subprocess' calls, all environment variables are passed to subprocesses by default. However, if you specifically do not want them to be passed to subprocesses, you may use 'env' argument in 'subprocess' calls. Due to the bug in Sentry SDK, with the Stdlib integration enabled (which is enabled by default), this expectation is not fulfilled, and all environment variables are being passed to subprocesses instead. 
As a workaround, and if passing environment variables to child processes poses a security risk for you, you can disable all default integrations.

Sentry-sdk 1.14.0 includes a fix for CVE-2023-28117: When using the Django integration of versions prior to 1.14.0 of the Sentry SDK in a specific configuration it is possible to leak sensitive cookies values, including the session cookie to Sentry. These sensitive cookies could then be used by someone with access to your Sentry issues to impersonate or escalate their privileges within your application. In order for these sensitive values to be leaked, the Sentry SDK configuration must have 'sendDefaultPII' set to 'True'; one must use a custom name for either 'SESSION_COOKIE_NAME' or 'CSRF_COOKIE_NAME' in one's Django settings; and one must not be configured in one's organization or project settings to use Sentry's data scrubbing features to account for the custom cookie names. As of version 1.14.0, the Django integration of the 'sentry-sdk' will detect the custom cookie names based on one's Django settings and will remove the values from the payload before sending the data to Sentry. As a workaround, use the SDK's filtering mechanism to remove the cookies from the payload that is sent to Sentry. For error events, this can be done with the 'before_send' callback method and for performance related events (transactions) one can use the 'before_send_transaction' callback method. Those who want to handle filtering of these values on the server-side can also use Sentry's advanced data scrubbing feature to account for the custom cookie names. Look for the '$http.cookies', '$http.headers', '$request.cookies', or '$request.headers' fields to target with a scrubbing rule.
https://github.com/getsentry/sentry-python/security/advisories/GHSA-29pr-6jr8-q5jm

Sentry-sdk 1.4.1 includes a fix for a Race Condition vulnerability.
https://github.com/getsentry/sentry-python/pull/1203

A SQL Injection issue in the SQL Panel in Jazzband Django Debug Toolbar before 1.11.1, 2.x before 2.2.1, and 3.x before 3.2.1 allows attackers to execute SQL statements by changing the raw_sql input field of the SQL explain, analyze, or select form. See CVE-2021-30459.

** DISPUTED ** Py throughout 1.11.0 allows remote attackers to conduct a ReDoS (Regular expression Denial of Service) attack via a Subversion repository with crafted info data because the InfoSvnCommand argument is mishandled.
https://github.com/pytest-dev/py/issues/287

Py 1.10.0 includes a fix for CVE-2020-29651: A denial of service via regular expression in the py.path.svnwc component of py (aka python-py) through 1.9.0 could be used by attackers to cause a compute-time denial of service attack by supplying malicious input to the blame functionality.

Affected versions of Idna are vulnerable to Denial Of Service via the idna.encode(), where a specially crafted argument could lead to significant resource consumption. In version 3.7, this function has been updated to reject such inputs efficiently, minimizing resource use. A practical workaround involves enforcing a maximum domain name length of 253 characters before encoding, as the vulnerability is triggered by unusually large inputs that normal operations wouldn't encounter.

** DISPUTED ** Py throughout 1.11.0 allows remote attackers to conduct a ReDoS (Regular expression Denial of Service) attack via a Subversion repository with crafted info data because the InfoSvnCommand argument is mishandled.
https://github.com/pytest-dev/py/issues/287

Py 1.10.0 includes a fix for CVE-2020-29651: A denial of service via regular expression in the py.path.svnwc component of py (aka python-py) through 1.9.0 could be used by attackers to cause a compute-time denial of service attack by supplying malicious input to the blame functionality.

An issue was discovered in Django 2.2 before 2.2.13 and 3.0 before 3.0.7. Query parameters generated by the Django admin ForeignKeyRawIdWidget were not properly URL encoded, leading to a possibility of an XSS attack.

Affected versions of the Django package are vulnerable to SQL Injection due to improper handling of control characters in column aliases within FilteredRelation. The FilteredRelation class fails to properly sanitize column aliases containing control characters when used with QuerySet methods annotate(), aggregate(), extra(), values(), values_list(), and alias() via dictionary expansion (**kwargs).

Affected versions of the Django package are vulnerable to SQL Injection due to improper sanitization of band index parameters in PostGIS raster lookups. The raster lookup functionality in Django's GIS module fails to properly validate or escape untrusted data used as a band index when performing spatial queries against PostGIS databases.

Affected versions of Django are vulnerable to potential denial-of-service in intcomma template filter when used with very long strings.

A potential denial-of-service vulnerability has been identified in Django's urlize() and urlizetrunc() functions in django.utils.html. This vulnerability can be triggered by inputting huge strings containing a specific sequence of characters.

Django 3.2.14 and 4.0.6 include a fix for CVE-2022-34265: Potential SQL injection via Trunc(kind) and Extract(lookup_name) arguments.
https://www.djangoproject.com/weblog/2022/jul/04/security-releases

An issue was discovered in Django 2.2 before 2.2.13 and 3.0 before 3.0.7. In cases where a memcached backend does not perform key validation, passing malformed cache keys could result in a key collision, and potential data leakage.

Django 4.1.7, 4.0.10 and 3.2.18 include a fix for CVE-2023-24580: Potential denial-of-service vulnerability in file uploads.
https://www.djangoproject.com/weblog/2023/feb/14/security-releases

An issue was discovered in Django 2.2 before 2.2.16, 3.0 before 3.0.10, and 3.1 before 3.1.1 (when Python 3.7+ is used). The intermediate-level directories of the filesystem cache had the system's standard umask rather than 0o077.

Django versions 3.2.2, 3.1.10 and 2.2.22 include a fix for CVE-2021-32052: In Django 2.2 before 2.2.22, 3.1 before 3.1.10, and 3.2 before 3.2.2 (with Python 3.9.5+), URLValidator does not prohibit newlines and tabs (unless the URLField form field is used). If an application uses values with newlines in an HTTP response, header injection can occur. Django itself is unaffected because HttpResponse prohibits newlines in HTTP headers.
https://www.djangoproject.com/weblog/2021/may/06/security-releases

Affected versions of the Django package are vulnerable to Path Traversal due to improper validation of file paths in the django.contrib.admindocs module. The `TemplateDetailView` view allows staff members to verify the existence of arbitrary files by manipulating the file path. An attacker with staff privileges can exploit this vulnerability to check for the presence of files outside the template root directories, and if the `admindocs` templates are customized to display file contents, they can also access the contents of these files.

Django addresses a memory exhaustion issue in django.utils.numberformat.floatformat(). When floatformat receives a string representation of a number in scientific notation with a large exponent, it could lead to excessive memory consumption. To prevent this, decimals with more than 200 digits are now returned as-is.

Django 2.2.24, 3.1.12, and 3.2.4 include a fix for CVE-2021-33571: In Django 2.2 before 2.2.24, 3.x before 3.1.12, and 3.2 before 3.2.4, URLValidator, validate_ipv4_address, and validate_ipv46_address do not prohibit leading zero characters in octal literals. This may allow a bypass of access control that is based on IP addresses. (validate_ipv4_address and validate_ipv46_address are unaffected with Python 3.9.5+).
https://www.djangoproject.com/weblog/2021/jun/02/security-releases

Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to inefficient string concatenation when processing duplicate HTTP headers in ASGI mode. The ASGIRequest class combines repeated headers using repeated string concatenation, resulting in super-linear (quadratic) time complexity when processing requests with many duplicate headers.

Affected versions of the Django package are vulnerable to SQL Injection due to improper handling of column aliases containing periods in QuerySet.order_by() when combined with FilteredRelation. The QuerySet.order_by() method fails to properly sanitize column aliases that contain periods when the same alias is used in FilteredRelation via dictionary expansion. 
https://github.com/django/django/commit/90f5b10784ba5bf369caed87640e2b4394ea3314

Django 2.2.21, 3.1.9 and 3.2.1 include a fix for CVE-2021-31542: MultiPartParser, UploadedFile, and FieldFile allowed directory traversal via uploaded files with suitably crafted file names.
https://www.djangoproject.com/weblog/2021/may/04/security-releases

An issue was discovered in Django 4.2 before 4.2.21, 5.1 before 5.1.9, and 5.2 before 5.2.1. The django.utils.html.strip_tags() function is vulnerable to a potential denial-of-service (slow performance) when processing inputs containing large sequences of incomplete HTML tags. The template filter striptags is also vulnerable, because it is built on top of strip_tags().

In Django 3.2 before 3.2.16, 4.0 before 4.0.8, and 4.1 before 4.1.2, internationalized URLs were subject to a potential denial of service attack via the locale parameter, which is treated as a regular expression.

Affected versions of Django are vulnerable to potential Denial of Service via certain inputs with a very large number of Unicode characters in django.utils.encoding.uri_to_iri().

Django 1.11.29, 2.2.11 and 3.0.4 includes a fix for CVE-2020-9402: Django 1.11 before 1.11.29, 2.2 before 2.2.11, and 3.0 before 3.0.4 allows SQL Injection if untrusted data is used as a tolerance parameter in GIS functions and aggregates on Oracle. By passing a suitably crafted tolerance to GIS functions and aggregates on Oracle, it was possible to break escaping and inject malicious SQL.
https://www.djangoproject.com/weblog/2020/mar/04/security-releases

Django affected versions are vulnerable to a potential SQL injection in the HasKey(lhs, rhs) lookup on Oracle databases. The vulnerability arises when untrusted data is directly used as the lhs value in the django.db.models.fields.json.HasKey lookup. However, applications using the jsonfield.has_key lookup with the __ syntax remain unaffected by this issue.

Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to quadratic time complexity during HTML parsing in text truncation methods. The django.utils.text.Truncator.chars() and Truncator.words() methods (with html=True), as well as the truncatechars_html and truncatewords_html template filters, exhibit quadratic time complexity when processing inputs containing a large number of unmatched HTML end tags.

Django versions 2.2.25, 3.1.14 and 3.2.10 include a fix for CVE-2021-44420: In Django 2.2 before 2.2.25, 3.1 before 3.1.14, and 3.2 before 3.2.10, HTTP requests for URLs with trailing newlines could bypass upstream access control based on URL paths.
https://www.djangoproject.com/weblog/2021/dec/07/security-releases/

Django 2.1.15 and 2.2.8 includes a fix for CVE-2019-19118: A Django model admin displaying inline related models, where the user has view-only permissions to a parent model but edit permissions to the inline model, would be presented with an editing UI, allowing POST requests, for updating the inline model. Directly editing the view-only parent model was not possible, but the parent model's save() method was called, triggering potential side effects, and causing pre and post-save signal handlers to be invoked. To resolve this, the Django admin is adjusted to require edit permissions on the parent model in order for inline models to be editable.

Django 1.11.27, 2.2.9 and 3.0.1 include a fix for CVE-2019-19844: Account takeover. A suitably crafted email address (that is equal to an existing user's email address after case transformation of Unicode characters) would allow an attacker to be sent a password reset token for the matched user account. One mitigation in the new releases is to send password reset tokens only to the registered user email address.

Django has a potential denial-of-service vulnerability in django.utils.html.urlize() and AdminURLFieldWidget. The urlize and urlizetrunc functions, along with AdminURLFieldWidget, are vulnerable to denial-of-service attacks when handling inputs with a very large number of Unicode characters.

Affected versions of Django are potentially vulnerable to denial-of-service via the get_supported_language_variant() method. This method was susceptible to a denial-of-service attack when used with very long strings containing specific characters. Exploiting this vulnerability could cause significant delays or crashes in the affected application, potentially leading to service disruption.

Django versions 2.2.19, 3.0.13 and 3.1.7 include a fix for CVE-2021-23336: Web cache poisoning via 'django.utils.http.limited_parse_qsl()'. Django contains a copy of 'urllib.parse.parse_qsl' which was added to backport some security fixes. A further security fix has been issued recently such that 'parse_qsl(' no longer allows using ';' as a query parameter separator by default.

Django 4.2.1, 4.1.9 and 3.2.19 include a fix for CVE-2023-31047: In Django 3.2 before 3.2.19, 4.x before 4.1.9, and 4.2 before 4.2.1, it was possible to bypass validation when using one form field to upload multiple files. This multiple upload has never been supported by forms.FileField or forms.ImageField (only the last uploaded file was validated). However, Django's "Uploading multiple files" documentation suggested otherwise.
https://www.djangoproject.com/weblog/2023/may/03/security-releases

Affected versions of Django are vulnerable to potential regular expression denial-of-service (REDoS). django.utils.text.Truncator.words() method (with html=True) and truncatewords_html template filter were subject to a potential regular expression denial-of-service attack using a suitably crafted string (follow up to CVE-2019-14232 and CVE-2023-43665).

Affected versions of Django are vulnerable to a potential ReDoS (regular expression denial of service) in EmailValidator and URLValidator via a very large number of domain name labels of emails and URLs.

Django 2.2.27, 3.2.12 and 4.0.2 include a fix for CVE-2022-23833: Denial-of-service possibility in file uploads.
https://www.djangoproject.com/weblog/2022/feb/01/security-releases

Django 2.2.28, 3.2.13 and 4.0.4 include a fix for CVE-2022-28346: An issue was discovered in Django 2.2 before 2.2.28, 3.2 before 3.2.13, and 4.0 before 4.0.4. QuerySet.annotate(), aggregate(), and extra() methods are subject to SQL injection in column aliases via a crafted dictionary (with dictionary expansion) as the passed **kwargs.
https://www.djangoproject.com/weblog/2022/apr/11/security-releases

In Django 2.2 before 2.2.20, 3.0 before 3.0.14, and 3.1 before 3.1.8, MultiPartParser allowed directory traversal via uploaded files with suitably crafted file names. Built-in upload handlers were not affected by this vulnerability.

CVE-2025-64458: Affected versions of the Django package are vulnerable to Denial of Service (DoS) due to slow Unicode NFKC normalization on Windows being applied to untrusted inputs. The django.contrib.auth.views.LoginView and django.contrib.auth.views.LogoutView, and django.views.i18n.set_language normalize user-controlled strings using Python’s NFKC algorithm, which is unusually slow on Windows for huge Unicode sequences and can be triggered to consume excessive CPU.

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45452: Storage.save in Django 2.2 before 2.2.26, 3.2 before 3.2.11, and 4.0 before 4.0.1 allows directory traversal if crafted filenames are directly passed to it.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases/

Affected versions of Django are vulnerable to a potential denial-of-service (DoS) attack in the `django.utils.html.strip_tags()` method. The vulnerability occurs when the `strip_tags()` method or the `striptags` template filter processes inputs containing large sequences of nested, incomplete HTML entities.

Affected versions of the Django package are vulnerable to Information Disclosure (Timing Attack) due to non-constant-time comparison in the mod_wsgi authentication handler. The django.contrib.auth.handlers.modwsgi.check_password() function does not perform user existence checks in constant time, allowing response timing differences to reveal whether usernames exist.

The {% debug %} template tag in Django 2.2 before 2.2.27, 3.2 before 3.2.12, and 4.0 before 4.0.2 does not properly encode the current context. This may lead to XSS.

Django fixes a potential denial-of-service vulnerability in XML ``Deserializer``.

An issue was discovered in Django 5.2 before 5.2.3, 5.1 before 5.1.11, and 4.2 before 4.2.23. Internal HTTP response logging does not escape request.path, which allows remote attackers to potentially manipulate log output via crafted URLs. This may lead to log injection or forgery when logs are viewed in terminals or processed by external systems.

Django 2.2.26, 3.2.11 and 4.0.1 include a fix for CVE-2021-45116: An issue was discovered in Django 2.2 before 2.2.26, 3.2 before 3.2.11, and 4.0 before 4.0.1. Due to leveraging the Django Template Language's variable resolution logic, the dictsort template filter was potentially vulnerable to information disclosure, or an unintended method call, if passed a suitably crafted key.
https://www.djangoproject.com/weblog/2022/jan/04/security-releases