Pillow 9.0.0 ensures JpegImagePlugin stops at the end of a truncated file to avoid Denial of Service attacks.
https://github.com/python-pillow/Pillow/pull/5921
https://github.com/advisories/GHSA-4fx9-vc88-q2xc

Pillow 10.0.1 updates its C dependency 'libwebp' to 1.3.2 to include a fix for a high-risk vulnerability.
https://pillow.readthedocs.io/en/stable/releasenotes/10.0.1.html

Pillow 9.0.0 excludes carriage return in PDF regex to help prevent ReDoS.
https://github.com/python-pillow/Pillow/pull/5912
https://github.com/python-pillow/Pillow/commit/43b800d933c996226e4d7df00c33fcbe46d97363

Pillow before 9.0.1 allows attackers to delete files because spaces in temporary pathnames are mishandled.

Pillow 9.0.0 includes a fix for CVE-2022-22815: path_getbbox in path.c in Pillow before 9.0.0 improperly initializes ImagePath.Path.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.0.html#fixed-imagepath-path-array-handling

Pillow 9.0.1 includes a fix for CVE-2022-22817: PIL.ImageMath.eval in Pillow before 9.0.0 allows evaluation of arbitrary expressions, such as ones that use the Python exec method. A first patch was issued for version 9.0.0 but it did not prevent builtins available to lambda expressions.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.1.html#security

Pillow 9.0.0 includes a fix for CVE-2022-22816: path_getbbox in path.c in Pillow before 9.0.0 has a buffer over-read during initialization of ImagePath.Path.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.0.html#fixed-imagepath-path-array-handling

Pillow 10.3.0 introduces a security update addressing CVE-2024-28219 by replacing certain functions with strncpy to prevent buffer overflow issues.

Pillow is affected by an arbitrary code execution vulnerability. If an attacker has control over the keys passed to the environment argument of PIL.ImageMath.eval(), they may be able to execute arbitrary code.
https://pillow.readthedocs.io/en/stable/releasenotes/10.2.0.html

Pillow 10.0.0 includes a fix for CVE-2023-44271: Denial of Service that uncontrollably allocates memory to process a given task, potentially causing a service to crash by having it run out of memory. This occurs for truetype in ImageFont when textlength in an ImageDraw instance operates on a long text argument.
https://github.com/python-pillow/Pillow/pull/7244

Pillow before 9.2.0 performs Improper Handling of Highly Compressed GIF Data (Data Amplification).

Pillow is potentially vulnerable to DoS attacks through PIL.ImageFont.ImageFont.getmask(). A decompression bomb check has also been added to the affected function.

When Tornado receives a request with two Transfer-Encoding: chunked headers, it ignores them both. This enables request smuggling when Tornado is deployed behind a proxy server that emits such requests. Pound does this.

Summary: Tornado's interpretation of symbols `-`, `+`, and `_` within chunk lengths and 'Content-Length' values contradicts the HTTP RFCs stipulations, potentially creating an avenue for request smuggling. This issue is generally found when Tornado operates behind specific proxies that understand these non-standard characters diversely, mostly observed in earlier versions of 'haproxy'; however, the latest version remains unaffected.

Details: Tornado utilizes the 'int' constructor to decipher the 'Content-Length' headers and chunk lengths in the locations mentioned below:

`tornado/http1connection.py:445`
Python3 code: self._expected_content_remaining = int(headers["Content-Length"])

`tornado/http1connection.py:621`
Python3 code: content_length = int(headers["Content-Length"])

`tornado/http1connection.py:671`
Python3 code: chunk_len = int(chunk_len_str.strip(), 16)

Notably, though the equation `int("0_0")` equates to `int("+0")`, `int("-0")`, and `int("0")`, using the 'int' constructor as a strategy for validating and parsing strings containing ASCII digits only is proven inadequate.

Tornado web framework affected versions contain a performance vulnerability in their HTTP cookie parser. When processing specially crafted malicious cookie headers, the parser's algorithm can exhibit quadratic time complexity. Since this parsing happens in the main event loop thread, it can cause the server to become unresponsive and block the processing of other incoming requests due to excessive CPU usage.

When Tornado's multipart/form-data parser encounters certain errors, it logs a warning but continues trying to parse the remainder of the data. This allows remote attackers to generate an extremely high volume of logs, constituting a DoS attack. This DoS is compounded by the fact that the logging subsystem is synchronous.

Tornado 6.3.2 includes a fix for CVE-2023-28370: Open redirect vulnerability in Tornado versions 6.3.1 and earlier allows a remote unauthenticated attacker to redirect a user to an arbitrary web site and conduct a phishing attack by having user access a specially crafted URL.

Tornado’s curl_httpclient.CurlAsyncHTTPClient class is vulnerable to CRLF (carriage return/line feed) injection in the request headers.

Hiredis (python wrapper for hiredis) 2.1.0 supports hiredis 1.1.0, that includes a security fix.
https://github.com/redis/hiredis-py/pull/135

An issue in Gevent before version 23.9.0 allows a remote attacker to escalate privileges via a crafted script to the WSGIServer component.

Affected versions of gevent are potentially vulnerable to a Race Condition leading to Unauthorized Access — CWE-362.

Affected versions of gevent were potentially vulnerable to HTTP request smuggling. The issue existed in the pywsgi Input._send_100_continue handling.

Affected versions of the Werkzeug package are vulnerable to Denial of Service (DoS) due to improper handling of Windows special device names in the safe_join function. In Werkzeug versions before 3.1.4, safe_join permits path segments such as “CON” or “AUX” to pass validation, allowing send_from_directory to construct a path that resolves to a Windows device file, which opens successfully but then blocks indefinitely when read.

Werkzeug 2.2.3 includes a fix for CVE-2023-25577: Prior to version 2.2.3, Werkzeug's multipart form data parser will parse an unlimited number of parts, including file parts. Parts can be a small amount of bytes, but each requires CPU time to parse and may use more memory as Python data. If a request can be made to an endpoint that accesses 'request.data', 'request.form', 'request.files', or 'request.get_data(parse_form_data=False)', it can cause unexpectedly high resource usage. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests. The amount of RAM required can trigger an out of memory kill of the process. Unlimited file parts can use up memory and file handles. If many concurrent requests are sent continuously, this can exhaust or kill all available workers.
https://github.com/pallets/werkzeug/security/advisories/GHSA-xg9f-g7g7-2323

Affected versions of Werkzeug are potentially vulnerable to resource exhaustion when parsing file data in forms. Applications using 'werkzeug.formparser.MultiPartParser' to parse 'multipart/form-data' requests (e.g. all flask applications) are vulnerable to a relatively simple but effective resource exhaustion (denial of service) attack. A specifically crafted form submission request can cause the parser to allocate and block 3 to 8 times the upload size in main memory. There is no upper limit; a single upload at 1 Gbit/s can exhaust 32 GB of RAM in less than 60 seconds.

Werkzeug 3.0.1 and 2.3.8 include a security fix: Slow multipart parsing for large parts potentially enabling DoS attacks.
https://github.com/pallets/werkzeug/commit/b1916c0c083e0be1c9d887ee2f3d696922bfc5c1

Werkzeug is a comprehensive WSGI web application library. If an upload of a file that starts with CR or LF and then is followed by megabytes of data without these characters: all of these bytes are appended chunk by chunk into internal bytearray and lookup for boundary is performed on growing buffer. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests.

Werkzeug 2.2.3 includes a fix for CVE-2023-23934: Browsers may allow "nameless" cookies that look like '=value' instead of 'key=value'. A vulnerable browser may allow a compromised application on an adjacent subdomain to exploit this to set a cookie like '=__Host-test=bad' for another subdomain. Werkzeug prior to 2.2.3 will parse the cookie '=__Host-test=bad' as __Host-test=bad'. If a Werkzeug application is running next to a vulnerable or malicious subdomain which sets such a cookie using a vulnerable browser, the Werkzeug application will see the bad cookie value but the valid cookie key.
https://github.com/pallets/werkzeug/security/advisories/GHSA-px8h-6qxv-m22q

Affected versions of Werkzeug are vulnerable to Path Traversal (CWE-22) on Windows systems running Python versions below 3.11. The safe_join() function failed to properly detect certain absolute paths on Windows, allowing attackers to potentially access files outside the intended directory. An attacker could craft special paths starting with "/" that bypass the directory restrictions on Windows systems. The vulnerability exists in the safe_join() function which relied solely on os.path.isabs() for path validation. This is exploitable on Windows systems by passing paths starting with "/" to safe_join(). To remediate, upgrade to the latest version which includes additional path validation checks. 
NOTE: This vulnerability specifically affects Windows systems running Python versions below 3.11 where ntpath.isabs() behavior differs.

Werkzeug is a comprehensive WSGI web application library. The debugger in affected versions of Werkzeug can allow an attacker to execute code on a developer's machine under some circumstances. This requires the attacker to get the developer to interact with a domain and subdomain they control, and enter the debugger PIN, but if they are successful it allows access to the debugger even if it is only running on localhost. This also requires the attacker to guess a URL in the developer's application that will trigger the debugger.

Sqlalchemy-utils from version 0.27.0 'EncryptedType' uses by default AES with CBC mode. The IV that it uses is not random though.
https://github.com/kvesteri/sqlalchemy-utils/issues/166
https://github.com/kvesteri/sqlalchemy-utils/pull/499

Pillow 9.0.0 ensures JpegImagePlugin stops at the end of a truncated file to avoid Denial of Service attacks.
https://github.com/python-pillow/Pillow/pull/5921
https://github.com/advisories/GHSA-4fx9-vc88-q2xc

Pillow 10.0.1 updates its C dependency 'libwebp' to 1.3.2 to include a fix for a high-risk vulnerability.
https://pillow.readthedocs.io/en/stable/releasenotes/10.0.1.html

Pillow 9.0.0 excludes carriage return in PDF regex to help prevent ReDoS.
https://github.com/python-pillow/Pillow/pull/5912
https://github.com/python-pillow/Pillow/commit/43b800d933c996226e4d7df00c33fcbe46d97363

Pillow before 9.0.1 allows attackers to delete files because spaces in temporary pathnames are mishandled.

Pillow 9.0.0 includes a fix for CVE-2022-22815: path_getbbox in path.c in Pillow before 9.0.0 improperly initializes ImagePath.Path.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.0.html#fixed-imagepath-path-array-handling

Pillow 9.0.1 includes a fix for CVE-2022-22817: PIL.ImageMath.eval in Pillow before 9.0.0 allows evaluation of arbitrary expressions, such as ones that use the Python exec method. A first patch was issued for version 9.0.0 but it did not prevent builtins available to lambda expressions.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.1.html#security

Pillow 9.0.0 includes a fix for CVE-2022-22816: path_getbbox in path.c in Pillow before 9.0.0 has a buffer over-read during initialization of ImagePath.Path.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.0.html#fixed-imagepath-path-array-handling

Pillow 10.3.0 introduces a security update addressing CVE-2024-28219 by replacing certain functions with strncpy to prevent buffer overflow issues.

Pillow is affected by an arbitrary code execution vulnerability. If an attacker has control over the keys passed to the environment argument of PIL.ImageMath.eval(), they may be able to execute arbitrary code.
https://pillow.readthedocs.io/en/stable/releasenotes/10.2.0.html

Pillow 10.0.0 includes a fix for CVE-2023-44271: Denial of Service that uncontrollably allocates memory to process a given task, potentially causing a service to crash by having it run out of memory. This occurs for truetype in ImageFont when textlength in an ImageDraw instance operates on a long text argument.
https://github.com/python-pillow/Pillow/pull/7244

Pillow before 9.2.0 performs Improper Handling of Highly Compressed GIF Data (Data Amplification).

Pillow is potentially vulnerable to DoS attacks through PIL.ImageFont.ImageFont.getmask(). A decompression bomb check has also been added to the affected function.

When Tornado receives a request with two Transfer-Encoding: chunked headers, it ignores them both. This enables request smuggling when Tornado is deployed behind a proxy server that emits such requests. Pound does this.

Summary: Tornado's interpretation of symbols `-`, `+`, and `_` within chunk lengths and 'Content-Length' values contradicts the HTTP RFCs stipulations, potentially creating an avenue for request smuggling. This issue is generally found when Tornado operates behind specific proxies that understand these non-standard characters diversely, mostly observed in earlier versions of 'haproxy'; however, the latest version remains unaffected.

Details: Tornado utilizes the 'int' constructor to decipher the 'Content-Length' headers and chunk lengths in the locations mentioned below:

`tornado/http1connection.py:445`
Python3 code: self._expected_content_remaining = int(headers["Content-Length"])

`tornado/http1connection.py:621`
Python3 code: content_length = int(headers["Content-Length"])

`tornado/http1connection.py:671`
Python3 code: chunk_len = int(chunk_len_str.strip(), 16)

Notably, though the equation `int("0_0")` equates to `int("+0")`, `int("-0")`, and `int("0")`, using the 'int' constructor as a strategy for validating and parsing strings containing ASCII digits only is proven inadequate.

Tornado web framework affected versions contain a performance vulnerability in their HTTP cookie parser. When processing specially crafted malicious cookie headers, the parser's algorithm can exhibit quadratic time complexity. Since this parsing happens in the main event loop thread, it can cause the server to become unresponsive and block the processing of other incoming requests due to excessive CPU usage.

When Tornado's multipart/form-data parser encounters certain errors, it logs a warning but continues trying to parse the remainder of the data. This allows remote attackers to generate an extremely high volume of logs, constituting a DoS attack. This DoS is compounded by the fact that the logging subsystem is synchronous.

Tornado 6.3.2 includes a fix for CVE-2023-28370: Open redirect vulnerability in Tornado versions 6.3.1 and earlier allows a remote unauthenticated attacker to redirect a user to an arbitrary web site and conduct a phishing attack by having user access a specially crafted URL.

Tornado’s curl_httpclient.CurlAsyncHTTPClient class is vulnerable to CRLF (carriage return/line feed) injection in the request headers.

Hiredis (python wrapper for hiredis) 2.1.0 supports hiredis 1.1.0, that includes a security fix.
https://github.com/redis/hiredis-py/pull/135

An issue in Gevent before version 23.9.0 allows a remote attacker to escalate privileges via a crafted script to the WSGIServer component.

Affected versions of gevent are potentially vulnerable to a Race Condition leading to Unauthorized Access — CWE-362.

Affected versions of gevent were potentially vulnerable to HTTP request smuggling. The issue existed in the pywsgi Input._send_100_continue handling.

Affected versions of the Werkzeug package are vulnerable to Denial of Service (DoS) due to improper handling of Windows special device names in the safe_join function. In Werkzeug versions before 3.1.4, safe_join permits path segments such as “CON” or “AUX” to pass validation, allowing send_from_directory to construct a path that resolves to a Windows device file, which opens successfully but then blocks indefinitely when read.

Werkzeug 2.2.3 includes a fix for CVE-2023-25577: Prior to version 2.2.3, Werkzeug's multipart form data parser will parse an unlimited number of parts, including file parts. Parts can be a small amount of bytes, but each requires CPU time to parse and may use more memory as Python data. If a request can be made to an endpoint that accesses 'request.data', 'request.form', 'request.files', or 'request.get_data(parse_form_data=False)', it can cause unexpectedly high resource usage. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests. The amount of RAM required can trigger an out of memory kill of the process. Unlimited file parts can use up memory and file handles. If many concurrent requests are sent continuously, this can exhaust or kill all available workers.
https://github.com/pallets/werkzeug/security/advisories/GHSA-xg9f-g7g7-2323

Affected versions of Werkzeug are potentially vulnerable to resource exhaustion when parsing file data in forms. Applications using 'werkzeug.formparser.MultiPartParser' to parse 'multipart/form-data' requests (e.g. all flask applications) are vulnerable to a relatively simple but effective resource exhaustion (denial of service) attack. A specifically crafted form submission request can cause the parser to allocate and block 3 to 8 times the upload size in main memory. There is no upper limit; a single upload at 1 Gbit/s can exhaust 32 GB of RAM in less than 60 seconds.

Werkzeug 3.0.1 and 2.3.8 include a security fix: Slow multipart parsing for large parts potentially enabling DoS attacks.
https://github.com/pallets/werkzeug/commit/b1916c0c083e0be1c9d887ee2f3d696922bfc5c1

Werkzeug is a comprehensive WSGI web application library. If an upload of a file that starts with CR or LF and then is followed by megabytes of data without these characters: all of these bytes are appended chunk by chunk into internal bytearray and lookup for boundary is performed on growing buffer. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests.

Werkzeug 2.2.3 includes a fix for CVE-2023-23934: Browsers may allow "nameless" cookies that look like '=value' instead of 'key=value'. A vulnerable browser may allow a compromised application on an adjacent subdomain to exploit this to set a cookie like '=__Host-test=bad' for another subdomain. Werkzeug prior to 2.2.3 will parse the cookie '=__Host-test=bad' as __Host-test=bad'. If a Werkzeug application is running next to a vulnerable or malicious subdomain which sets such a cookie using a vulnerable browser, the Werkzeug application will see the bad cookie value but the valid cookie key.
https://github.com/pallets/werkzeug/security/advisories/GHSA-px8h-6qxv-m22q

Affected versions of Werkzeug are vulnerable to Path Traversal (CWE-22) on Windows systems running Python versions below 3.11. The safe_join() function failed to properly detect certain absolute paths on Windows, allowing attackers to potentially access files outside the intended directory. An attacker could craft special paths starting with "/" that bypass the directory restrictions on Windows systems. The vulnerability exists in the safe_join() function which relied solely on os.path.isabs() for path validation. This is exploitable on Windows systems by passing paths starting with "/" to safe_join(). To remediate, upgrade to the latest version which includes additional path validation checks. 
NOTE: This vulnerability specifically affects Windows systems running Python versions below 3.11 where ntpath.isabs() behavior differs.

Werkzeug is a comprehensive WSGI web application library. The debugger in affected versions of Werkzeug can allow an attacker to execute code on a developer's machine under some circumstances. This requires the attacker to get the developer to interact with a domain and subdomain they control, and enter the debugger PIN, but if they are successful it allows access to the debugger even if it is only running on localhost. This also requires the attacker to guess a URL in the developer's application that will trigger the debugger.

Sqlalchemy-utils from version 0.27.0 'EncryptedType' uses by default AES with CBC mode. The IV that it uses is not random though.
https://github.com/kvesteri/sqlalchemy-utils/issues/166
https://github.com/kvesteri/sqlalchemy-utils/pull/499

Flask 2.2.5 and 2.3.2 include a fix for CVE-2023-30861: When all of the following conditions are met, a response containing data intended for one client may be cached and subsequently sent by the proxy to other clients. If the proxy also caches 'Set-Cookie' headers, it may send one client's 'session' cookie to other clients. The severity depends on the application's use of the session and the proxy's behavior regarding cookies. The risk depends on all these conditions being met:
1. The application must be hosted behind a caching proxy that does not strip cookies or ignore responses with cookies.
2. The application sets 'session.permanent = True'
3. The application does not access or modify the session at any point during a request.
4. 'SESSION_REFRESH_EACH_REQUEST' enabled (the default).
5. The application does not set a 'Cache-Control' header to indicate that a page is private or should not be cached.
This happens because vulnerable versions of Flask only set the 'Vary: Cookie' header when the session is accessed or modified, not when it is refreshed (re-sent to update the expiration) without being accessed or modified.
https://github.com/pallets/flask/security/advisories/GHSA-m2qf-hxjv-5gpq

Pillow 9.0.0 ensures JpegImagePlugin stops at the end of a truncated file to avoid Denial of Service attacks.
https://github.com/python-pillow/Pillow/pull/5921
https://github.com/advisories/GHSA-4fx9-vc88-q2xc

Pillow 10.0.1 updates its C dependency 'libwebp' to 1.3.2 to include a fix for a high-risk vulnerability.
https://pillow.readthedocs.io/en/stable/releasenotes/10.0.1.html

Pillow 9.0.0 excludes carriage return in PDF regex to help prevent ReDoS.
https://github.com/python-pillow/Pillow/pull/5912
https://github.com/python-pillow/Pillow/commit/43b800d933c996226e4d7df00c33fcbe46d97363

Pillow before 9.0.1 allows attackers to delete files because spaces in temporary pathnames are mishandled.

Pillow 9.0.0 includes a fix for CVE-2022-22815: path_getbbox in path.c in Pillow before 9.0.0 improperly initializes ImagePath.Path.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.0.html#fixed-imagepath-path-array-handling

Pillow 9.0.1 includes a fix for CVE-2022-22817: PIL.ImageMath.eval in Pillow before 9.0.0 allows evaluation of arbitrary expressions, such as ones that use the Python exec method. A first patch was issued for version 9.0.0 but it did not prevent builtins available to lambda expressions.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.1.html#security

Pillow 9.0.0 includes a fix for CVE-2022-22816: path_getbbox in path.c in Pillow before 9.0.0 has a buffer over-read during initialization of ImagePath.Path.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.0.html#fixed-imagepath-path-array-handling

Pillow 10.3.0 introduces a security update addressing CVE-2024-28219 by replacing certain functions with strncpy to prevent buffer overflow issues.

Pillow is affected by an arbitrary code execution vulnerability. If an attacker has control over the keys passed to the environment argument of PIL.ImageMath.eval(), they may be able to execute arbitrary code.
https://pillow.readthedocs.io/en/stable/releasenotes/10.2.0.html

Pillow 10.0.0 includes a fix for CVE-2023-44271: Denial of Service that uncontrollably allocates memory to process a given task, potentially causing a service to crash by having it run out of memory. This occurs for truetype in ImageFont when textlength in an ImageDraw instance operates on a long text argument.
https://github.com/python-pillow/Pillow/pull/7244

Pillow before 9.2.0 performs Improper Handling of Highly Compressed GIF Data (Data Amplification).

Pillow is potentially vulnerable to DoS attacks through PIL.ImageFont.ImageFont.getmask(). A decompression bomb check has also been added to the affected function.

When Tornado receives a request with two Transfer-Encoding: chunked headers, it ignores them both. This enables request smuggling when Tornado is deployed behind a proxy server that emits such requests. Pound does this.

Summary: Tornado's interpretation of symbols `-`, `+`, and `_` within chunk lengths and 'Content-Length' values contradicts the HTTP RFCs stipulations, potentially creating an avenue for request smuggling. This issue is generally found when Tornado operates behind specific proxies that understand these non-standard characters diversely, mostly observed in earlier versions of 'haproxy'; however, the latest version remains unaffected.

Details: Tornado utilizes the 'int' constructor to decipher the 'Content-Length' headers and chunk lengths in the locations mentioned below:

`tornado/http1connection.py:445`
Python3 code: self._expected_content_remaining = int(headers["Content-Length"])

`tornado/http1connection.py:621`
Python3 code: content_length = int(headers["Content-Length"])

`tornado/http1connection.py:671`
Python3 code: chunk_len = int(chunk_len_str.strip(), 16)

Notably, though the equation `int("0_0")` equates to `int("+0")`, `int("-0")`, and `int("0")`, using the 'int' constructor as a strategy for validating and parsing strings containing ASCII digits only is proven inadequate.

Tornado web framework affected versions contain a performance vulnerability in their HTTP cookie parser. When processing specially crafted malicious cookie headers, the parser's algorithm can exhibit quadratic time complexity. Since this parsing happens in the main event loop thread, it can cause the server to become unresponsive and block the processing of other incoming requests due to excessive CPU usage.

When Tornado's multipart/form-data parser encounters certain errors, it logs a warning but continues trying to parse the remainder of the data. This allows remote attackers to generate an extremely high volume of logs, constituting a DoS attack. This DoS is compounded by the fact that the logging subsystem is synchronous.

Tornado 6.3.2 includes a fix for CVE-2023-28370: Open redirect vulnerability in Tornado versions 6.3.1 and earlier allows a remote unauthenticated attacker to redirect a user to an arbitrary web site and conduct a phishing attack by having user access a specially crafted URL.

Tornado’s curl_httpclient.CurlAsyncHTTPClient class is vulnerable to CRLF (carriage return/line feed) injection in the request headers.

Hiredis (python wrapper for hiredis) 2.1.0 supports hiredis 1.1.0, that includes a security fix.
https://github.com/redis/hiredis-py/pull/135

An issue in Gevent before version 23.9.0 allows a remote attacker to escalate privileges via a crafted script to the WSGIServer component.

Affected versions of gevent are potentially vulnerable to a Race Condition leading to Unauthorized Access — CWE-362.

Affected versions of gevent were potentially vulnerable to HTTP request smuggling. The issue existed in the pywsgi Input._send_100_continue handling.

Affected versions of the Werkzeug package are vulnerable to Denial of Service (DoS) due to improper handling of Windows special device names in the safe_join function. In Werkzeug versions before 3.1.4, safe_join permits path segments such as “CON” or “AUX” to pass validation, allowing send_from_directory to construct a path that resolves to a Windows device file, which opens successfully but then blocks indefinitely when read.

Werkzeug 2.2.3 includes a fix for CVE-2023-25577: Prior to version 2.2.3, Werkzeug's multipart form data parser will parse an unlimited number of parts, including file parts. Parts can be a small amount of bytes, but each requires CPU time to parse and may use more memory as Python data. If a request can be made to an endpoint that accesses 'request.data', 'request.form', 'request.files', or 'request.get_data(parse_form_data=False)', it can cause unexpectedly high resource usage. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests. The amount of RAM required can trigger an out of memory kill of the process. Unlimited file parts can use up memory and file handles. If many concurrent requests are sent continuously, this can exhaust or kill all available workers.
https://github.com/pallets/werkzeug/security/advisories/GHSA-xg9f-g7g7-2323

Affected versions of Werkzeug are potentially vulnerable to resource exhaustion when parsing file data in forms. Applications using 'werkzeug.formparser.MultiPartParser' to parse 'multipart/form-data' requests (e.g. all flask applications) are vulnerable to a relatively simple but effective resource exhaustion (denial of service) attack. A specifically crafted form submission request can cause the parser to allocate and block 3 to 8 times the upload size in main memory. There is no upper limit; a single upload at 1 Gbit/s can exhaust 32 GB of RAM in less than 60 seconds.

Werkzeug 3.0.1 and 2.3.8 include a security fix: Slow multipart parsing for large parts potentially enabling DoS attacks.
https://github.com/pallets/werkzeug/commit/b1916c0c083e0be1c9d887ee2f3d696922bfc5c1

Werkzeug is a comprehensive WSGI web application library. If an upload of a file that starts with CR or LF and then is followed by megabytes of data without these characters: all of these bytes are appended chunk by chunk into internal bytearray and lookup for boundary is performed on growing buffer. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests.

Werkzeug 2.2.3 includes a fix for CVE-2023-23934: Browsers may allow "nameless" cookies that look like '=value' instead of 'key=value'. A vulnerable browser may allow a compromised application on an adjacent subdomain to exploit this to set a cookie like '=__Host-test=bad' for another subdomain. Werkzeug prior to 2.2.3 will parse the cookie '=__Host-test=bad' as __Host-test=bad'. If a Werkzeug application is running next to a vulnerable or malicious subdomain which sets such a cookie using a vulnerable browser, the Werkzeug application will see the bad cookie value but the valid cookie key.
https://github.com/pallets/werkzeug/security/advisories/GHSA-px8h-6qxv-m22q

Affected versions of Werkzeug are vulnerable to Path Traversal (CWE-22) on Windows systems running Python versions below 3.11. The safe_join() function failed to properly detect certain absolute paths on Windows, allowing attackers to potentially access files outside the intended directory. An attacker could craft special paths starting with "/" that bypass the directory restrictions on Windows systems. The vulnerability exists in the safe_join() function which relied solely on os.path.isabs() for path validation. This is exploitable on Windows systems by passing paths starting with "/" to safe_join(). To remediate, upgrade to the latest version which includes additional path validation checks. 
NOTE: This vulnerability specifically affects Windows systems running Python versions below 3.11 where ntpath.isabs() behavior differs.

Werkzeug is a comprehensive WSGI web application library. The debugger in affected versions of Werkzeug can allow an attacker to execute code on a developer's machine under some circumstances. This requires the attacker to get the developer to interact with a domain and subdomain they control, and enter the debugger PIN, but if they are successful it allows access to the debugger even if it is only running on localhost. This also requires the attacker to guess a URL in the developer's application that will trigger the debugger.

Sqlalchemy-utils from version 0.27.0 'EncryptedType' uses by default AES with CBC mode. The IV that it uses is not random though.
https://github.com/kvesteri/sqlalchemy-utils/issues/166
https://github.com/kvesteri/sqlalchemy-utils/pull/499

Lxml 4.9.1 includes a fix for CVE-2022-2309: NULL Pointer Dereference allows attackers to cause a denial of service (or application crash). This only applies when lxml is used together with libxml2 2.9.10 through 2.9.14. libxml2 2.9.9 and earlier are not affected. It allows triggering crashes through forged input data, given a vulnerable code sequence in the application. The vulnerability is caused by the iterwalk function (also used by the canonicalize function). Such code shouldn't be in wide-spread use, given that parsing + iterwalk would usually be replaced with the more efficient iterparse function. However, an XML converter that serialises to C14N would also be vulnerable, for example, and there are legitimate use cases for this code sequence. If untrusted input is received (also remotely) and processed via iterwalk function, a crash can be triggered.

Flask 2.2.5 and 2.3.2 include a fix for CVE-2023-30861: When all of the following conditions are met, a response containing data intended for one client may be cached and subsequently sent by the proxy to other clients. If the proxy also caches 'Set-Cookie' headers, it may send one client's 'session' cookie to other clients. The severity depends on the application's use of the session and the proxy's behavior regarding cookies. The risk depends on all these conditions being met:
1. The application must be hosted behind a caching proxy that does not strip cookies or ignore responses with cookies.
2. The application sets 'session.permanent = True'
3. The application does not access or modify the session at any point during a request.
4. 'SESSION_REFRESH_EACH_REQUEST' enabled (the default).
5. The application does not set a 'Cache-Control' header to indicate that a page is private or should not be cached.
This happens because vulnerable versions of Flask only set the 'Vary: Cookie' header when the session is accessed or modified, not when it is refreshed (re-sent to update the expiration) without being accessed or modified.
https://github.com/pallets/flask/security/advisories/GHSA-m2qf-hxjv-5gpq

Pillow 9.0.0 ensures JpegImagePlugin stops at the end of a truncated file to avoid Denial of Service attacks.
https://github.com/python-pillow/Pillow/pull/5921
https://github.com/advisories/GHSA-4fx9-vc88-q2xc

Pillow 10.0.1 updates its C dependency 'libwebp' to 1.3.2 to include a fix for a high-risk vulnerability.
https://pillow.readthedocs.io/en/stable/releasenotes/10.0.1.html

Pillow 9.0.0 excludes carriage return in PDF regex to help prevent ReDoS.
https://github.com/python-pillow/Pillow/pull/5912
https://github.com/python-pillow/Pillow/commit/43b800d933c996226e4d7df00c33fcbe46d97363

Pillow before 9.0.1 allows attackers to delete files because spaces in temporary pathnames are mishandled.

Pillow 9.0.0 includes a fix for CVE-2022-22815: path_getbbox in path.c in Pillow before 9.0.0 improperly initializes ImagePath.Path.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.0.html#fixed-imagepath-path-array-handling

Pillow 9.0.1 includes a fix for CVE-2022-22817: PIL.ImageMath.eval in Pillow before 9.0.0 allows evaluation of arbitrary expressions, such as ones that use the Python exec method. A first patch was issued for version 9.0.0 but it did not prevent builtins available to lambda expressions.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.1.html#security

Pillow 9.0.0 includes a fix for CVE-2022-22816: path_getbbox in path.c in Pillow before 9.0.0 has a buffer over-read during initialization of ImagePath.Path.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.0.html#fixed-imagepath-path-array-handling

Pillow 10.3.0 introduces a security update addressing CVE-2024-28219 by replacing certain functions with strncpy to prevent buffer overflow issues.

Pillow is affected by an arbitrary code execution vulnerability. If an attacker has control over the keys passed to the environment argument of PIL.ImageMath.eval(), they may be able to execute arbitrary code.
https://pillow.readthedocs.io/en/stable/releasenotes/10.2.0.html

Pillow 10.0.0 includes a fix for CVE-2023-44271: Denial of Service that uncontrollably allocates memory to process a given task, potentially causing a service to crash by having it run out of memory. This occurs for truetype in ImageFont when textlength in an ImageDraw instance operates on a long text argument.
https://github.com/python-pillow/Pillow/pull/7244

Pillow before 9.2.0 performs Improper Handling of Highly Compressed GIF Data (Data Amplification).

Pillow is potentially vulnerable to DoS attacks through PIL.ImageFont.ImageFont.getmask(). A decompression bomb check has also been added to the affected function.

When Tornado receives a request with two Transfer-Encoding: chunked headers, it ignores them both. This enables request smuggling when Tornado is deployed behind a proxy server that emits such requests. Pound does this.

Summary: Tornado's interpretation of symbols `-`, `+`, and `_` within chunk lengths and 'Content-Length' values contradicts the HTTP RFCs stipulations, potentially creating an avenue for request smuggling. This issue is generally found when Tornado operates behind specific proxies that understand these non-standard characters diversely, mostly observed in earlier versions of 'haproxy'; however, the latest version remains unaffected.

Details: Tornado utilizes the 'int' constructor to decipher the 'Content-Length' headers and chunk lengths in the locations mentioned below:

`tornado/http1connection.py:445`
Python3 code: self._expected_content_remaining = int(headers["Content-Length"])

`tornado/http1connection.py:621`
Python3 code: content_length = int(headers["Content-Length"])

`tornado/http1connection.py:671`
Python3 code: chunk_len = int(chunk_len_str.strip(), 16)

Notably, though the equation `int("0_0")` equates to `int("+0")`, `int("-0")`, and `int("0")`, using the 'int' constructor as a strategy for validating and parsing strings containing ASCII digits only is proven inadequate.

Tornado web framework affected versions contain a performance vulnerability in their HTTP cookie parser. When processing specially crafted malicious cookie headers, the parser's algorithm can exhibit quadratic time complexity. Since this parsing happens in the main event loop thread, it can cause the server to become unresponsive and block the processing of other incoming requests due to excessive CPU usage.

When Tornado's multipart/form-data parser encounters certain errors, it logs a warning but continues trying to parse the remainder of the data. This allows remote attackers to generate an extremely high volume of logs, constituting a DoS attack. This DoS is compounded by the fact that the logging subsystem is synchronous.

Tornado 6.3.2 includes a fix for CVE-2023-28370: Open redirect vulnerability in Tornado versions 6.3.1 and earlier allows a remote unauthenticated attacker to redirect a user to an arbitrary web site and conduct a phishing attack by having user access a specially crafted URL.

Tornado’s curl_httpclient.CurlAsyncHTTPClient class is vulnerable to CRLF (carriage return/line feed) injection in the request headers.

Hiredis (python wrapper for hiredis) 2.1.0 supports hiredis 1.1.0, that includes a security fix.
https://github.com/redis/hiredis-py/pull/135

An issue in Gevent before version 23.9.0 allows a remote attacker to escalate privileges via a crafted script to the WSGIServer component.

Affected versions of gevent are potentially vulnerable to a Race Condition leading to Unauthorized Access — CWE-362.

Affected versions of gevent were potentially vulnerable to HTTP request smuggling. The issue existed in the pywsgi Input._send_100_continue handling.

Affected versions of the Werkzeug package are vulnerable to Denial of Service (DoS) due to improper handling of Windows special device names in the safe_join function. In Werkzeug versions before 3.1.4, safe_join permits path segments such as “CON” or “AUX” to pass validation, allowing send_from_directory to construct a path that resolves to a Windows device file, which opens successfully but then blocks indefinitely when read.

Werkzeug 2.2.3 includes a fix for CVE-2023-25577: Prior to version 2.2.3, Werkzeug's multipart form data parser will parse an unlimited number of parts, including file parts. Parts can be a small amount of bytes, but each requires CPU time to parse and may use more memory as Python data. If a request can be made to an endpoint that accesses 'request.data', 'request.form', 'request.files', or 'request.get_data(parse_form_data=False)', it can cause unexpectedly high resource usage. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests. The amount of RAM required can trigger an out of memory kill of the process. Unlimited file parts can use up memory and file handles. If many concurrent requests are sent continuously, this can exhaust or kill all available workers.
https://github.com/pallets/werkzeug/security/advisories/GHSA-xg9f-g7g7-2323

Affected versions of Werkzeug are potentially vulnerable to resource exhaustion when parsing file data in forms. Applications using 'werkzeug.formparser.MultiPartParser' to parse 'multipart/form-data' requests (e.g. all flask applications) are vulnerable to a relatively simple but effective resource exhaustion (denial of service) attack. A specifically crafted form submission request can cause the parser to allocate and block 3 to 8 times the upload size in main memory. There is no upper limit; a single upload at 1 Gbit/s can exhaust 32 GB of RAM in less than 60 seconds.

Werkzeug 3.0.1 and 2.3.8 include a security fix: Slow multipart parsing for large parts potentially enabling DoS attacks.
https://github.com/pallets/werkzeug/commit/b1916c0c083e0be1c9d887ee2f3d696922bfc5c1

Werkzeug is a comprehensive WSGI web application library. If an upload of a file that starts with CR or LF and then is followed by megabytes of data without these characters: all of these bytes are appended chunk by chunk into internal bytearray and lookup for boundary is performed on growing buffer. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests.

Werkzeug 2.2.3 includes a fix for CVE-2023-23934: Browsers may allow "nameless" cookies that look like '=value' instead of 'key=value'. A vulnerable browser may allow a compromised application on an adjacent subdomain to exploit this to set a cookie like '=__Host-test=bad' for another subdomain. Werkzeug prior to 2.2.3 will parse the cookie '=__Host-test=bad' as __Host-test=bad'. If a Werkzeug application is running next to a vulnerable or malicious subdomain which sets such a cookie using a vulnerable browser, the Werkzeug application will see the bad cookie value but the valid cookie key.
https://github.com/pallets/werkzeug/security/advisories/GHSA-px8h-6qxv-m22q

Affected versions of Werkzeug are vulnerable to Path Traversal (CWE-22) on Windows systems running Python versions below 3.11. The safe_join() function failed to properly detect certain absolute paths on Windows, allowing attackers to potentially access files outside the intended directory. An attacker could craft special paths starting with "/" that bypass the directory restrictions on Windows systems. The vulnerability exists in the safe_join() function which relied solely on os.path.isabs() for path validation. This is exploitable on Windows systems by passing paths starting with "/" to safe_join(). To remediate, upgrade to the latest version which includes additional path validation checks. 
NOTE: This vulnerability specifically affects Windows systems running Python versions below 3.11 where ntpath.isabs() behavior differs.

Werkzeug is a comprehensive WSGI web application library. The debugger in affected versions of Werkzeug can allow an attacker to execute code on a developer's machine under some circumstances. This requires the attacker to get the developer to interact with a domain and subdomain they control, and enter the debugger PIN, but if they are successful it allows access to the debugger even if it is only running on localhost. This also requires the attacker to guess a URL in the developer's application that will trigger the debugger.

Sqlalchemy-utils from version 0.27.0 'EncryptedType' uses by default AES with CBC mode. The IV that it uses is not random though.
https://github.com/kvesteri/sqlalchemy-utils/issues/166
https://github.com/kvesteri/sqlalchemy-utils/pull/499

Lxml 4.9.1 includes a fix for CVE-2022-2309: NULL Pointer Dereference allows attackers to cause a denial of service (or application crash). This only applies when lxml is used together with libxml2 2.9.10 through 2.9.14. libxml2 2.9.9 and earlier are not affected. It allows triggering crashes through forged input data, given a vulnerable code sequence in the application. The vulnerability is caused by the iterwalk function (also used by the canonicalize function). Such code shouldn't be in wide-spread use, given that parsing + iterwalk would usually be replaced with the more efficient iterparse function. However, an XML converter that serialises to C14N would also be vulnerable, for example, and there are legitimate use cases for this code sequence. If untrusted input is received (also remotely) and processed via iterwalk function, a crash can be triggered.

Flask 2.2.5 and 2.3.2 include a fix for CVE-2023-30861: When all of the following conditions are met, a response containing data intended for one client may be cached and subsequently sent by the proxy to other clients. If the proxy also caches 'Set-Cookie' headers, it may send one client's 'session' cookie to other clients. The severity depends on the application's use of the session and the proxy's behavior regarding cookies. The risk depends on all these conditions being met:
1. The application must be hosted behind a caching proxy that does not strip cookies or ignore responses with cookies.
2. The application sets 'session.permanent = True'
3. The application does not access or modify the session at any point during a request.
4. 'SESSION_REFRESH_EACH_REQUEST' enabled (the default).
5. The application does not set a 'Cache-Control' header to indicate that a page is private or should not be cached.
This happens because vulnerable versions of Flask only set the 'Vary: Cookie' header when the session is accessed or modified, not when it is refreshed (re-sent to update the expiration) without being accessed or modified.
https://github.com/pallets/flask/security/advisories/GHSA-m2qf-hxjv-5gpq

Pillow 9.0.0 ensures JpegImagePlugin stops at the end of a truncated file to avoid Denial of Service attacks.
https://github.com/python-pillow/Pillow/pull/5921
https://github.com/advisories/GHSA-4fx9-vc88-q2xc

Pillow 10.0.1 updates its C dependency 'libwebp' to 1.3.2 to include a fix for a high-risk vulnerability.
https://pillow.readthedocs.io/en/stable/releasenotes/10.0.1.html

Pillow 9.0.0 excludes carriage return in PDF regex to help prevent ReDoS.
https://github.com/python-pillow/Pillow/pull/5912
https://github.com/python-pillow/Pillow/commit/43b800d933c996226e4d7df00c33fcbe46d97363

Pillow before 9.0.1 allows attackers to delete files because spaces in temporary pathnames are mishandled.

Pillow 9.0.0 includes a fix for CVE-2022-22815: path_getbbox in path.c in Pillow before 9.0.0 improperly initializes ImagePath.Path.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.0.html#fixed-imagepath-path-array-handling

Pillow 9.0.1 includes a fix for CVE-2022-22817: PIL.ImageMath.eval in Pillow before 9.0.0 allows evaluation of arbitrary expressions, such as ones that use the Python exec method. A first patch was issued for version 9.0.0 but it did not prevent builtins available to lambda expressions.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.1.html#security

Pillow 9.0.0 includes a fix for CVE-2022-22816: path_getbbox in path.c in Pillow before 9.0.0 has a buffer over-read during initialization of ImagePath.Path.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.0.html#fixed-imagepath-path-array-handling

Pillow 10.3.0 introduces a security update addressing CVE-2024-28219 by replacing certain functions with strncpy to prevent buffer overflow issues.

Pillow is affected by an arbitrary code execution vulnerability. If an attacker has control over the keys passed to the environment argument of PIL.ImageMath.eval(), they may be able to execute arbitrary code.
https://pillow.readthedocs.io/en/stable/releasenotes/10.2.0.html

Pillow 10.0.0 includes a fix for CVE-2023-44271: Denial of Service that uncontrollably allocates memory to process a given task, potentially causing a service to crash by having it run out of memory. This occurs for truetype in ImageFont when textlength in an ImageDraw instance operates on a long text argument.
https://github.com/python-pillow/Pillow/pull/7244

Pillow before 9.2.0 performs Improper Handling of Highly Compressed GIF Data (Data Amplification).

Pillow is potentially vulnerable to DoS attacks through PIL.ImageFont.ImageFont.getmask(). A decompression bomb check has also been added to the affected function.

When Tornado receives a request with two Transfer-Encoding: chunked headers, it ignores them both. This enables request smuggling when Tornado is deployed behind a proxy server that emits such requests. Pound does this.

Summary: Tornado's interpretation of symbols `-`, `+`, and `_` within chunk lengths and 'Content-Length' values contradicts the HTTP RFCs stipulations, potentially creating an avenue for request smuggling. This issue is generally found when Tornado operates behind specific proxies that understand these non-standard characters diversely, mostly observed in earlier versions of 'haproxy'; however, the latest version remains unaffected.

Details: Tornado utilizes the 'int' constructor to decipher the 'Content-Length' headers and chunk lengths in the locations mentioned below:

`tornado/http1connection.py:445`
Python3 code: self._expected_content_remaining = int(headers["Content-Length"])

`tornado/http1connection.py:621`
Python3 code: content_length = int(headers["Content-Length"])

`tornado/http1connection.py:671`
Python3 code: chunk_len = int(chunk_len_str.strip(), 16)

Notably, though the equation `int("0_0")` equates to `int("+0")`, `int("-0")`, and `int("0")`, using the 'int' constructor as a strategy for validating and parsing strings containing ASCII digits only is proven inadequate.

Tornado web framework affected versions contain a performance vulnerability in their HTTP cookie parser. When processing specially crafted malicious cookie headers, the parser's algorithm can exhibit quadratic time complexity. Since this parsing happens in the main event loop thread, it can cause the server to become unresponsive and block the processing of other incoming requests due to excessive CPU usage.

When Tornado's multipart/form-data parser encounters certain errors, it logs a warning but continues trying to parse the remainder of the data. This allows remote attackers to generate an extremely high volume of logs, constituting a DoS attack. This DoS is compounded by the fact that the logging subsystem is synchronous.

Tornado 6.3.2 includes a fix for CVE-2023-28370: Open redirect vulnerability in Tornado versions 6.3.1 and earlier allows a remote unauthenticated attacker to redirect a user to an arbitrary web site and conduct a phishing attack by having user access a specially crafted URL.

Tornado’s curl_httpclient.CurlAsyncHTTPClient class is vulnerable to CRLF (carriage return/line feed) injection in the request headers.

Hiredis (python wrapper for hiredis) 2.1.0 supports hiredis 1.1.0, that includes a security fix.
https://github.com/redis/hiredis-py/pull/135

An issue in Gevent before version 23.9.0 allows a remote attacker to escalate privileges via a crafted script to the WSGIServer component.

Affected versions of gevent are potentially vulnerable to a Race Condition leading to Unauthorized Access — CWE-362.

Affected versions of gevent were potentially vulnerable to HTTP request smuggling. The issue existed in the pywsgi Input._send_100_continue handling.

Affected versions of the Werkzeug package are vulnerable to Denial of Service (DoS) due to improper handling of Windows special device names in the safe_join function. In Werkzeug versions before 3.1.4, safe_join permits path segments such as “CON” or “AUX” to pass validation, allowing send_from_directory to construct a path that resolves to a Windows device file, which opens successfully but then blocks indefinitely when read.

Werkzeug 2.2.3 includes a fix for CVE-2023-25577: Prior to version 2.2.3, Werkzeug's multipart form data parser will parse an unlimited number of parts, including file parts. Parts can be a small amount of bytes, but each requires CPU time to parse and may use more memory as Python data. If a request can be made to an endpoint that accesses 'request.data', 'request.form', 'request.files', or 'request.get_data(parse_form_data=False)', it can cause unexpectedly high resource usage. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests. The amount of RAM required can trigger an out of memory kill of the process. Unlimited file parts can use up memory and file handles. If many concurrent requests are sent continuously, this can exhaust or kill all available workers.
https://github.com/pallets/werkzeug/security/advisories/GHSA-xg9f-g7g7-2323

Affected versions of Werkzeug are potentially vulnerable to resource exhaustion when parsing file data in forms. Applications using 'werkzeug.formparser.MultiPartParser' to parse 'multipart/form-data' requests (e.g. all flask applications) are vulnerable to a relatively simple but effective resource exhaustion (denial of service) attack. A specifically crafted form submission request can cause the parser to allocate and block 3 to 8 times the upload size in main memory. There is no upper limit; a single upload at 1 Gbit/s can exhaust 32 GB of RAM in less than 60 seconds.

Werkzeug 3.0.1 and 2.3.8 include a security fix: Slow multipart parsing for large parts potentially enabling DoS attacks.
https://github.com/pallets/werkzeug/commit/b1916c0c083e0be1c9d887ee2f3d696922bfc5c1

Werkzeug is a comprehensive WSGI web application library. If an upload of a file that starts with CR or LF and then is followed by megabytes of data without these characters: all of these bytes are appended chunk by chunk into internal bytearray and lookup for boundary is performed on growing buffer. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests.

Werkzeug 2.2.3 includes a fix for CVE-2023-23934: Browsers may allow "nameless" cookies that look like '=value' instead of 'key=value'. A vulnerable browser may allow a compromised application on an adjacent subdomain to exploit this to set a cookie like '=__Host-test=bad' for another subdomain. Werkzeug prior to 2.2.3 will parse the cookie '=__Host-test=bad' as __Host-test=bad'. If a Werkzeug application is running next to a vulnerable or malicious subdomain which sets such a cookie using a vulnerable browser, the Werkzeug application will see the bad cookie value but the valid cookie key.
https://github.com/pallets/werkzeug/security/advisories/GHSA-px8h-6qxv-m22q

Affected versions of Werkzeug are vulnerable to Path Traversal (CWE-22) on Windows systems running Python versions below 3.11. The safe_join() function failed to properly detect certain absolute paths on Windows, allowing attackers to potentially access files outside the intended directory. An attacker could craft special paths starting with "/" that bypass the directory restrictions on Windows systems. The vulnerability exists in the safe_join() function which relied solely on os.path.isabs() for path validation. This is exploitable on Windows systems by passing paths starting with "/" to safe_join(). To remediate, upgrade to the latest version which includes additional path validation checks. 
NOTE: This vulnerability specifically affects Windows systems running Python versions below 3.11 where ntpath.isabs() behavior differs.

Werkzeug is a comprehensive WSGI web application library. The debugger in affected versions of Werkzeug can allow an attacker to execute code on a developer's machine under some circumstances. This requires the attacker to get the developer to interact with a domain and subdomain they control, and enter the debugger PIN, but if they are successful it allows access to the debugger even if it is only running on localhost. This also requires the attacker to guess a URL in the developer's application that will trigger the debugger.

Sqlalchemy-utils from version 0.27.0 'EncryptedType' uses by default AES with CBC mode. The IV that it uses is not random though.
https://github.com/kvesteri/sqlalchemy-utils/issues/166
https://github.com/kvesteri/sqlalchemy-utils/pull/499

Lxml 4.9.1 includes a fix for CVE-2022-2309: NULL Pointer Dereference allows attackers to cause a denial of service (or application crash). This only applies when lxml is used together with libxml2 2.9.10 through 2.9.14. libxml2 2.9.9 and earlier are not affected. It allows triggering crashes through forged input data, given a vulnerable code sequence in the application. The vulnerability is caused by the iterwalk function (also used by the canonicalize function). Such code shouldn't be in wide-spread use, given that parsing + iterwalk would usually be replaced with the more efficient iterparse function. However, an XML converter that serialises to C14N would also be vulnerable, for example, and there are legitimate use cases for this code sequence. If untrusted input is received (also remotely) and processed via iterwalk function, a crash can be triggered.

Flask 2.2.5 and 2.3.2 include a fix for CVE-2023-30861: When all of the following conditions are met, a response containing data intended for one client may be cached and subsequently sent by the proxy to other clients. If the proxy also caches 'Set-Cookie' headers, it may send one client's 'session' cookie to other clients. The severity depends on the application's use of the session and the proxy's behavior regarding cookies. The risk depends on all these conditions being met:
1. The application must be hosted behind a caching proxy that does not strip cookies or ignore responses with cookies.
2. The application sets 'session.permanent = True'
3. The application does not access or modify the session at any point during a request.
4. 'SESSION_REFRESH_EACH_REQUEST' enabled (the default).
5. The application does not set a 'Cache-Control' header to indicate that a page is private or should not be cached.
This happens because vulnerable versions of Flask only set the 'Vary: Cookie' header when the session is accessed or modified, not when it is refreshed (re-sent to update the expiration) without being accessed or modified.
https://github.com/pallets/flask/security/advisories/GHSA-m2qf-hxjv-5gpq

Pillow 9.0.0 ensures JpegImagePlugin stops at the end of a truncated file to avoid Denial of Service attacks.
https://github.com/python-pillow/Pillow/pull/5921
https://github.com/advisories/GHSA-4fx9-vc88-q2xc

Pillow 10.0.1 updates its C dependency 'libwebp' to 1.3.2 to include a fix for a high-risk vulnerability.
https://pillow.readthedocs.io/en/stable/releasenotes/10.0.1.html

Pillow 9.0.0 excludes carriage return in PDF regex to help prevent ReDoS.
https://github.com/python-pillow/Pillow/pull/5912
https://github.com/python-pillow/Pillow/commit/43b800d933c996226e4d7df00c33fcbe46d97363

Pillow before 9.0.1 allows attackers to delete files because spaces in temporary pathnames are mishandled.

Pillow 9.0.0 includes a fix for CVE-2022-22815: path_getbbox in path.c in Pillow before 9.0.0 improperly initializes ImagePath.Path.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.0.html#fixed-imagepath-path-array-handling

Pillow 9.0.1 includes a fix for CVE-2022-22817: PIL.ImageMath.eval in Pillow before 9.0.0 allows evaluation of arbitrary expressions, such as ones that use the Python exec method. A first patch was issued for version 9.0.0 but it did not prevent builtins available to lambda expressions.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.1.html#security

Pillow 9.0.0 includes a fix for CVE-2022-22816: path_getbbox in path.c in Pillow before 9.0.0 has a buffer over-read during initialization of ImagePath.Path.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.0.html#fixed-imagepath-path-array-handling

Pillow 10.3.0 introduces a security update addressing CVE-2024-28219 by replacing certain functions with strncpy to prevent buffer overflow issues.

Pillow is affected by an arbitrary code execution vulnerability. If an attacker has control over the keys passed to the environment argument of PIL.ImageMath.eval(), they may be able to execute arbitrary code.
https://pillow.readthedocs.io/en/stable/releasenotes/10.2.0.html

Pillow 10.0.0 includes a fix for CVE-2023-44271: Denial of Service that uncontrollably allocates memory to process a given task, potentially causing a service to crash by having it run out of memory. This occurs for truetype in ImageFont when textlength in an ImageDraw instance operates on a long text argument.
https://github.com/python-pillow/Pillow/pull/7244

Pillow before 9.2.0 performs Improper Handling of Highly Compressed GIF Data (Data Amplification).

Pillow is potentially vulnerable to DoS attacks through PIL.ImageFont.ImageFont.getmask(). A decompression bomb check has also been added to the affected function.

When Tornado receives a request with two Transfer-Encoding: chunked headers, it ignores them both. This enables request smuggling when Tornado is deployed behind a proxy server that emits such requests. Pound does this.

Summary: Tornado's interpretation of symbols `-`, `+`, and `_` within chunk lengths and 'Content-Length' values contradicts the HTTP RFCs stipulations, potentially creating an avenue for request smuggling. This issue is generally found when Tornado operates behind specific proxies that understand these non-standard characters diversely, mostly observed in earlier versions of 'haproxy'; however, the latest version remains unaffected.

Details: Tornado utilizes the 'int' constructor to decipher the 'Content-Length' headers and chunk lengths in the locations mentioned below:

`tornado/http1connection.py:445`
Python3 code: self._expected_content_remaining = int(headers["Content-Length"])

`tornado/http1connection.py:621`
Python3 code: content_length = int(headers["Content-Length"])

`tornado/http1connection.py:671`
Python3 code: chunk_len = int(chunk_len_str.strip(), 16)

Notably, though the equation `int("0_0")` equates to `int("+0")`, `int("-0")`, and `int("0")`, using the 'int' constructor as a strategy for validating and parsing strings containing ASCII digits only is proven inadequate.

Tornado web framework affected versions contain a performance vulnerability in their HTTP cookie parser. When processing specially crafted malicious cookie headers, the parser's algorithm can exhibit quadratic time complexity. Since this parsing happens in the main event loop thread, it can cause the server to become unresponsive and block the processing of other incoming requests due to excessive CPU usage.

When Tornado's multipart/form-data parser encounters certain errors, it logs a warning but continues trying to parse the remainder of the data. This allows remote attackers to generate an extremely high volume of logs, constituting a DoS attack. This DoS is compounded by the fact that the logging subsystem is synchronous.

Tornado 6.3.2 includes a fix for CVE-2023-28370: Open redirect vulnerability in Tornado versions 6.3.1 and earlier allows a remote unauthenticated attacker to redirect a user to an arbitrary web site and conduct a phishing attack by having user access a specially crafted URL.

Tornado’s curl_httpclient.CurlAsyncHTTPClient class is vulnerable to CRLF (carriage return/line feed) injection in the request headers.

Hiredis (python wrapper for hiredis) 2.1.0 supports hiredis 1.1.0, that includes a security fix.
https://github.com/redis/hiredis-py/pull/135

An issue in Gevent before version 23.9.0 allows a remote attacker to escalate privileges via a crafted script to the WSGIServer component.

Affected versions of gevent are potentially vulnerable to a Race Condition leading to Unauthorized Access — CWE-362.

Affected versions of gevent were potentially vulnerable to HTTP request smuggling. The issue existed in the pywsgi Input._send_100_continue handling.

Affected versions of the Werkzeug package are vulnerable to Denial of Service (DoS) due to improper handling of Windows special device names in the safe_join function. In Werkzeug versions before 3.1.4, safe_join permits path segments such as “CON” or “AUX” to pass validation, allowing send_from_directory to construct a path that resolves to a Windows device file, which opens successfully but then blocks indefinitely when read.

Werkzeug 2.2.3 includes a fix for CVE-2023-25577: Prior to version 2.2.3, Werkzeug's multipart form data parser will parse an unlimited number of parts, including file parts. Parts can be a small amount of bytes, but each requires CPU time to parse and may use more memory as Python data. If a request can be made to an endpoint that accesses 'request.data', 'request.form', 'request.files', or 'request.get_data(parse_form_data=False)', it can cause unexpectedly high resource usage. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests. The amount of RAM required can trigger an out of memory kill of the process. Unlimited file parts can use up memory and file handles. If many concurrent requests are sent continuously, this can exhaust or kill all available workers.
https://github.com/pallets/werkzeug/security/advisories/GHSA-xg9f-g7g7-2323

Affected versions of Werkzeug are potentially vulnerable to resource exhaustion when parsing file data in forms. Applications using 'werkzeug.formparser.MultiPartParser' to parse 'multipart/form-data' requests (e.g. all flask applications) are vulnerable to a relatively simple but effective resource exhaustion (denial of service) attack. A specifically crafted form submission request can cause the parser to allocate and block 3 to 8 times the upload size in main memory. There is no upper limit; a single upload at 1 Gbit/s can exhaust 32 GB of RAM in less than 60 seconds.

Werkzeug 3.0.1 and 2.3.8 include a security fix: Slow multipart parsing for large parts potentially enabling DoS attacks.
https://github.com/pallets/werkzeug/commit/b1916c0c083e0be1c9d887ee2f3d696922bfc5c1

Werkzeug is a comprehensive WSGI web application library. If an upload of a file that starts with CR or LF and then is followed by megabytes of data without these characters: all of these bytes are appended chunk by chunk into internal bytearray and lookup for boundary is performed on growing buffer. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests.

Werkzeug 2.2.3 includes a fix for CVE-2023-23934: Browsers may allow "nameless" cookies that look like '=value' instead of 'key=value'. A vulnerable browser may allow a compromised application on an adjacent subdomain to exploit this to set a cookie like '=__Host-test=bad' for another subdomain. Werkzeug prior to 2.2.3 will parse the cookie '=__Host-test=bad' as __Host-test=bad'. If a Werkzeug application is running next to a vulnerable or malicious subdomain which sets such a cookie using a vulnerable browser, the Werkzeug application will see the bad cookie value but the valid cookie key.
https://github.com/pallets/werkzeug/security/advisories/GHSA-px8h-6qxv-m22q

Affected versions of Werkzeug are vulnerable to Path Traversal (CWE-22) on Windows systems running Python versions below 3.11. The safe_join() function failed to properly detect certain absolute paths on Windows, allowing attackers to potentially access files outside the intended directory. An attacker could craft special paths starting with "/" that bypass the directory restrictions on Windows systems. The vulnerability exists in the safe_join() function which relied solely on os.path.isabs() for path validation. This is exploitable on Windows systems by passing paths starting with "/" to safe_join(). To remediate, upgrade to the latest version which includes additional path validation checks. 
NOTE: This vulnerability specifically affects Windows systems running Python versions below 3.11 where ntpath.isabs() behavior differs.

Werkzeug is a comprehensive WSGI web application library. The debugger in affected versions of Werkzeug can allow an attacker to execute code on a developer's machine under some circumstances. This requires the attacker to get the developer to interact with a domain and subdomain they control, and enter the debugger PIN, but if they are successful it allows access to the debugger even if it is only running on localhost. This also requires the attacker to guess a URL in the developer's application that will trigger the debugger.

Sqlalchemy-utils from version 0.27.0 'EncryptedType' uses by default AES with CBC mode. The IV that it uses is not random though.
https://github.com/kvesteri/sqlalchemy-utils/issues/166
https://github.com/kvesteri/sqlalchemy-utils/pull/499

Lxml 4.9.1 includes a fix for CVE-2022-2309: NULL Pointer Dereference allows attackers to cause a denial of service (or application crash). This only applies when lxml is used together with libxml2 2.9.10 through 2.9.14. libxml2 2.9.9 and earlier are not affected. It allows triggering crashes through forged input data, given a vulnerable code sequence in the application. The vulnerability is caused by the iterwalk function (also used by the canonicalize function). Such code shouldn't be in wide-spread use, given that parsing + iterwalk would usually be replaced with the more efficient iterparse function. However, an XML converter that serialises to C14N would also be vulnerable, for example, and there are legitimate use cases for this code sequence. If untrusted input is received (also remotely) and processed via iterwalk function, a crash can be triggered.

Flask 2.2.5 and 2.3.2 include a fix for CVE-2023-30861: When all of the following conditions are met, a response containing data intended for one client may be cached and subsequently sent by the proxy to other clients. If the proxy also caches 'Set-Cookie' headers, it may send one client's 'session' cookie to other clients. The severity depends on the application's use of the session and the proxy's behavior regarding cookies. The risk depends on all these conditions being met:
1. The application must be hosted behind a caching proxy that does not strip cookies or ignore responses with cookies.
2. The application sets 'session.permanent = True'
3. The application does not access or modify the session at any point during a request.
4. 'SESSION_REFRESH_EACH_REQUEST' enabled (the default).
5. The application does not set a 'Cache-Control' header to indicate that a page is private or should not be cached.
This happens because vulnerable versions of Flask only set the 'Vary: Cookie' header when the session is accessed or modified, not when it is refreshed (re-sent to update the expiration) without being accessed or modified.
https://github.com/pallets/flask/security/advisories/GHSA-m2qf-hxjv-5gpq

Pillow 9.0.0 ensures JpegImagePlugin stops at the end of a truncated file to avoid Denial of Service attacks.
https://github.com/python-pillow/Pillow/pull/5921
https://github.com/advisories/GHSA-4fx9-vc88-q2xc

Pillow 10.0.1 updates its C dependency 'libwebp' to 1.3.2 to include a fix for a high-risk vulnerability.
https://pillow.readthedocs.io/en/stable/releasenotes/10.0.1.html

Pillow 9.0.0 excludes carriage return in PDF regex to help prevent ReDoS.
https://github.com/python-pillow/Pillow/pull/5912
https://github.com/python-pillow/Pillow/commit/43b800d933c996226e4d7df00c33fcbe46d97363

Pillow before 9.0.1 allows attackers to delete files because spaces in temporary pathnames are mishandled.

Pillow 9.0.0 includes a fix for CVE-2022-22815: path_getbbox in path.c in Pillow before 9.0.0 improperly initializes ImagePath.Path.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.0.html#fixed-imagepath-path-array-handling

Pillow 9.0.1 includes a fix for CVE-2022-22817: PIL.ImageMath.eval in Pillow before 9.0.0 allows evaluation of arbitrary expressions, such as ones that use the Python exec method. A first patch was issued for version 9.0.0 but it did not prevent builtins available to lambda expressions.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.1.html#security

Pillow 9.0.0 includes a fix for CVE-2022-22816: path_getbbox in path.c in Pillow before 9.0.0 has a buffer over-read during initialization of ImagePath.Path.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.0.html#fixed-imagepath-path-array-handling

Pillow 10.3.0 introduces a security update addressing CVE-2024-28219 by replacing certain functions with strncpy to prevent buffer overflow issues.

Pillow is affected by an arbitrary code execution vulnerability. If an attacker has control over the keys passed to the environment argument of PIL.ImageMath.eval(), they may be able to execute arbitrary code.
https://pillow.readthedocs.io/en/stable/releasenotes/10.2.0.html

Pillow 10.0.0 includes a fix for CVE-2023-44271: Denial of Service that uncontrollably allocates memory to process a given task, potentially causing a service to crash by having it run out of memory. This occurs for truetype in ImageFont when textlength in an ImageDraw instance operates on a long text argument.
https://github.com/python-pillow/Pillow/pull/7244

Pillow before 9.2.0 performs Improper Handling of Highly Compressed GIF Data (Data Amplification).

Pillow is potentially vulnerable to DoS attacks through PIL.ImageFont.ImageFont.getmask(). A decompression bomb check has also been added to the affected function.

When Tornado receives a request with two Transfer-Encoding: chunked headers, it ignores them both. This enables request smuggling when Tornado is deployed behind a proxy server that emits such requests. Pound does this.

Summary: Tornado's interpretation of symbols `-`, `+`, and `_` within chunk lengths and 'Content-Length' values contradicts the HTTP RFCs stipulations, potentially creating an avenue for request smuggling. This issue is generally found when Tornado operates behind specific proxies that understand these non-standard characters diversely, mostly observed in earlier versions of 'haproxy'; however, the latest version remains unaffected.

Details: Tornado utilizes the 'int' constructor to decipher the 'Content-Length' headers and chunk lengths in the locations mentioned below:

`tornado/http1connection.py:445`
Python3 code: self._expected_content_remaining = int(headers["Content-Length"])

`tornado/http1connection.py:621`
Python3 code: content_length = int(headers["Content-Length"])

`tornado/http1connection.py:671`
Python3 code: chunk_len = int(chunk_len_str.strip(), 16)

Notably, though the equation `int("0_0")` equates to `int("+0")`, `int("-0")`, and `int("0")`, using the 'int' constructor as a strategy for validating and parsing strings containing ASCII digits only is proven inadequate.

Tornado web framework affected versions contain a performance vulnerability in their HTTP cookie parser. When processing specially crafted malicious cookie headers, the parser's algorithm can exhibit quadratic time complexity. Since this parsing happens in the main event loop thread, it can cause the server to become unresponsive and block the processing of other incoming requests due to excessive CPU usage.

When Tornado's multipart/form-data parser encounters certain errors, it logs a warning but continues trying to parse the remainder of the data. This allows remote attackers to generate an extremely high volume of logs, constituting a DoS attack. This DoS is compounded by the fact that the logging subsystem is synchronous.

Tornado 6.3.2 includes a fix for CVE-2023-28370: Open redirect vulnerability in Tornado versions 6.3.1 and earlier allows a remote unauthenticated attacker to redirect a user to an arbitrary web site and conduct a phishing attack by having user access a specially crafted URL.

Tornado’s curl_httpclient.CurlAsyncHTTPClient class is vulnerable to CRLF (carriage return/line feed) injection in the request headers.

Hiredis (python wrapper for hiredis) 2.1.0 supports hiredis 1.1.0, that includes a security fix.
https://github.com/redis/hiredis-py/pull/135

An issue in Gevent before version 23.9.0 allows a remote attacker to escalate privileges via a crafted script to the WSGIServer component.

Affected versions of gevent are potentially vulnerable to a Race Condition leading to Unauthorized Access — CWE-362.

Affected versions of gevent were potentially vulnerable to HTTP request smuggling. The issue existed in the pywsgi Input._send_100_continue handling.

Affected versions of the Werkzeug package are vulnerable to Denial of Service (DoS) due to improper handling of Windows special device names in the safe_join function. In Werkzeug versions before 3.1.4, safe_join permits path segments such as “CON” or “AUX” to pass validation, allowing send_from_directory to construct a path that resolves to a Windows device file, which opens successfully but then blocks indefinitely when read.

Werkzeug 2.2.3 includes a fix for CVE-2023-25577: Prior to version 2.2.3, Werkzeug's multipart form data parser will parse an unlimited number of parts, including file parts. Parts can be a small amount of bytes, but each requires CPU time to parse and may use more memory as Python data. If a request can be made to an endpoint that accesses 'request.data', 'request.form', 'request.files', or 'request.get_data(parse_form_data=False)', it can cause unexpectedly high resource usage. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests. The amount of RAM required can trigger an out of memory kill of the process. Unlimited file parts can use up memory and file handles. If many concurrent requests are sent continuously, this can exhaust or kill all available workers.
https://github.com/pallets/werkzeug/security/advisories/GHSA-xg9f-g7g7-2323

Affected versions of Werkzeug are potentially vulnerable to resource exhaustion when parsing file data in forms. Applications using 'werkzeug.formparser.MultiPartParser' to parse 'multipart/form-data' requests (e.g. all flask applications) are vulnerable to a relatively simple but effective resource exhaustion (denial of service) attack. A specifically crafted form submission request can cause the parser to allocate and block 3 to 8 times the upload size in main memory. There is no upper limit; a single upload at 1 Gbit/s can exhaust 32 GB of RAM in less than 60 seconds.

Werkzeug 3.0.1 and 2.3.8 include a security fix: Slow multipart parsing for large parts potentially enabling DoS attacks.
https://github.com/pallets/werkzeug/commit/b1916c0c083e0be1c9d887ee2f3d696922bfc5c1

Werkzeug is a comprehensive WSGI web application library. If an upload of a file that starts with CR or LF and then is followed by megabytes of data without these characters: all of these bytes are appended chunk by chunk into internal bytearray and lookup for boundary is performed on growing buffer. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests.

Werkzeug 2.2.3 includes a fix for CVE-2023-23934: Browsers may allow "nameless" cookies that look like '=value' instead of 'key=value'. A vulnerable browser may allow a compromised application on an adjacent subdomain to exploit this to set a cookie like '=__Host-test=bad' for another subdomain. Werkzeug prior to 2.2.3 will parse the cookie '=__Host-test=bad' as __Host-test=bad'. If a Werkzeug application is running next to a vulnerable or malicious subdomain which sets such a cookie using a vulnerable browser, the Werkzeug application will see the bad cookie value but the valid cookie key.
https://github.com/pallets/werkzeug/security/advisories/GHSA-px8h-6qxv-m22q

Affected versions of Werkzeug are vulnerable to Path Traversal (CWE-22) on Windows systems running Python versions below 3.11. The safe_join() function failed to properly detect certain absolute paths on Windows, allowing attackers to potentially access files outside the intended directory. An attacker could craft special paths starting with "/" that bypass the directory restrictions on Windows systems. The vulnerability exists in the safe_join() function which relied solely on os.path.isabs() for path validation. This is exploitable on Windows systems by passing paths starting with "/" to safe_join(). To remediate, upgrade to the latest version which includes additional path validation checks. 
NOTE: This vulnerability specifically affects Windows systems running Python versions below 3.11 where ntpath.isabs() behavior differs.

Werkzeug is a comprehensive WSGI web application library. The debugger in affected versions of Werkzeug can allow an attacker to execute code on a developer's machine under some circumstances. This requires the attacker to get the developer to interact with a domain and subdomain they control, and enter the debugger PIN, but if they are successful it allows access to the debugger even if it is only running on localhost. This also requires the attacker to guess a URL in the developer's application that will trigger the debugger.

Sqlalchemy-utils from version 0.27.0 'EncryptedType' uses by default AES with CBC mode. The IV that it uses is not random though.
https://github.com/kvesteri/sqlalchemy-utils/issues/166
https://github.com/kvesteri/sqlalchemy-utils/pull/499

Lxml 4.9.1 includes a fix for CVE-2022-2309: NULL Pointer Dereference allows attackers to cause a denial of service (or application crash). This only applies when lxml is used together with libxml2 2.9.10 through 2.9.14. libxml2 2.9.9 and earlier are not affected. It allows triggering crashes through forged input data, given a vulnerable code sequence in the application. The vulnerability is caused by the iterwalk function (also used by the canonicalize function). Such code shouldn't be in wide-spread use, given that parsing + iterwalk would usually be replaced with the more efficient iterparse function. However, an XML converter that serialises to C14N would also be vulnerable, for example, and there are legitimate use cases for this code sequence. If untrusted input is received (also remotely) and processed via iterwalk function, a crash can be triggered.

Flask 2.2.5 and 2.3.2 include a fix for CVE-2023-30861: When all of the following conditions are met, a response containing data intended for one client may be cached and subsequently sent by the proxy to other clients. If the proxy also caches 'Set-Cookie' headers, it may send one client's 'session' cookie to other clients. The severity depends on the application's use of the session and the proxy's behavior regarding cookies. The risk depends on all these conditions being met:
1. The application must be hosted behind a caching proxy that does not strip cookies or ignore responses with cookies.
2. The application sets 'session.permanent = True'
3. The application does not access or modify the session at any point during a request.
4. 'SESSION_REFRESH_EACH_REQUEST' enabled (the default).
5. The application does not set a 'Cache-Control' header to indicate that a page is private or should not be cached.
This happens because vulnerable versions of Flask only set the 'Vary: Cookie' header when the session is accessed or modified, not when it is refreshed (re-sent to update the expiration) without being accessed or modified.
https://github.com/pallets/flask/security/advisories/GHSA-m2qf-hxjv-5gpq

Pillow 9.0.0 ensures JpegImagePlugin stops at the end of a truncated file to avoid Denial of Service attacks.
https://github.com/python-pillow/Pillow/pull/5921
https://github.com/advisories/GHSA-4fx9-vc88-q2xc

Pillow 10.0.1 updates its C dependency 'libwebp' to 1.3.2 to include a fix for a high-risk vulnerability.
https://pillow.readthedocs.io/en/stable/releasenotes/10.0.1.html

Pillow 9.0.0 excludes carriage return in PDF regex to help prevent ReDoS.
https://github.com/python-pillow/Pillow/pull/5912
https://github.com/python-pillow/Pillow/commit/43b800d933c996226e4d7df00c33fcbe46d97363

Pillow before 9.0.1 allows attackers to delete files because spaces in temporary pathnames are mishandled.

Pillow 9.0.0 includes a fix for CVE-2022-22815: path_getbbox in path.c in Pillow before 9.0.0 improperly initializes ImagePath.Path.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.0.html#fixed-imagepath-path-array-handling

Pillow 9.0.1 includes a fix for CVE-2022-22817: PIL.ImageMath.eval in Pillow before 9.0.0 allows evaluation of arbitrary expressions, such as ones that use the Python exec method. A first patch was issued for version 9.0.0 but it did not prevent builtins available to lambda expressions.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.1.html#security

Pillow 9.0.0 includes a fix for CVE-2022-22816: path_getbbox in path.c in Pillow before 9.0.0 has a buffer over-read during initialization of ImagePath.Path.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.0.html#fixed-imagepath-path-array-handling

Pillow 10.3.0 introduces a security update addressing CVE-2024-28219 by replacing certain functions with strncpy to prevent buffer overflow issues.

Pillow is affected by an arbitrary code execution vulnerability. If an attacker has control over the keys passed to the environment argument of PIL.ImageMath.eval(), they may be able to execute arbitrary code.
https://pillow.readthedocs.io/en/stable/releasenotes/10.2.0.html

Pillow 10.0.0 includes a fix for CVE-2023-44271: Denial of Service that uncontrollably allocates memory to process a given task, potentially causing a service to crash by having it run out of memory. This occurs for truetype in ImageFont when textlength in an ImageDraw instance operates on a long text argument.
https://github.com/python-pillow/Pillow/pull/7244

Pillow before 9.2.0 performs Improper Handling of Highly Compressed GIF Data (Data Amplification).

Pillow is potentially vulnerable to DoS attacks through PIL.ImageFont.ImageFont.getmask(). A decompression bomb check has also been added to the affected function.

When Tornado receives a request with two Transfer-Encoding: chunked headers, it ignores them both. This enables request smuggling when Tornado is deployed behind a proxy server that emits such requests. Pound does this.

Summary: Tornado's interpretation of symbols `-`, `+`, and `_` within chunk lengths and 'Content-Length' values contradicts the HTTP RFCs stipulations, potentially creating an avenue for request smuggling. This issue is generally found when Tornado operates behind specific proxies that understand these non-standard characters diversely, mostly observed in earlier versions of 'haproxy'; however, the latest version remains unaffected.

Details: Tornado utilizes the 'int' constructor to decipher the 'Content-Length' headers and chunk lengths in the locations mentioned below:

`tornado/http1connection.py:445`
Python3 code: self._expected_content_remaining = int(headers["Content-Length"])

`tornado/http1connection.py:621`
Python3 code: content_length = int(headers["Content-Length"])

`tornado/http1connection.py:671`
Python3 code: chunk_len = int(chunk_len_str.strip(), 16)

Notably, though the equation `int("0_0")` equates to `int("+0")`, `int("-0")`, and `int("0")`, using the 'int' constructor as a strategy for validating and parsing strings containing ASCII digits only is proven inadequate.

Tornado web framework affected versions contain a performance vulnerability in their HTTP cookie parser. When processing specially crafted malicious cookie headers, the parser's algorithm can exhibit quadratic time complexity. Since this parsing happens in the main event loop thread, it can cause the server to become unresponsive and block the processing of other incoming requests due to excessive CPU usage.

When Tornado's multipart/form-data parser encounters certain errors, it logs a warning but continues trying to parse the remainder of the data. This allows remote attackers to generate an extremely high volume of logs, constituting a DoS attack. This DoS is compounded by the fact that the logging subsystem is synchronous.

Tornado 6.3.2 includes a fix for CVE-2023-28370: Open redirect vulnerability in Tornado versions 6.3.1 and earlier allows a remote unauthenticated attacker to redirect a user to an arbitrary web site and conduct a phishing attack by having user access a specially crafted URL.

Tornado’s curl_httpclient.CurlAsyncHTTPClient class is vulnerable to CRLF (carriage return/line feed) injection in the request headers.

Hiredis (python wrapper for hiredis) 2.1.0 supports hiredis 1.1.0, that includes a security fix.
https://github.com/redis/hiredis-py/pull/135

An issue in Gevent before version 23.9.0 allows a remote attacker to escalate privileges via a crafted script to the WSGIServer component.

Affected versions of gevent are potentially vulnerable to a Race Condition leading to Unauthorized Access — CWE-362.

Affected versions of gevent were potentially vulnerable to HTTP request smuggling. The issue existed in the pywsgi Input._send_100_continue handling.

Affected versions of the Werkzeug package are vulnerable to Denial of Service (DoS) due to improper handling of Windows special device names in the safe_join function. In Werkzeug versions before 3.1.4, safe_join permits path segments such as “CON” or “AUX” to pass validation, allowing send_from_directory to construct a path that resolves to a Windows device file, which opens successfully but then blocks indefinitely when read.

Werkzeug 2.2.3 includes a fix for CVE-2023-25577: Prior to version 2.2.3, Werkzeug's multipart form data parser will parse an unlimited number of parts, including file parts. Parts can be a small amount of bytes, but each requires CPU time to parse and may use more memory as Python data. If a request can be made to an endpoint that accesses 'request.data', 'request.form', 'request.files', or 'request.get_data(parse_form_data=False)', it can cause unexpectedly high resource usage. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests. The amount of RAM required can trigger an out of memory kill of the process. Unlimited file parts can use up memory and file handles. If many concurrent requests are sent continuously, this can exhaust or kill all available workers.
https://github.com/pallets/werkzeug/security/advisories/GHSA-xg9f-g7g7-2323

Affected versions of Werkzeug are potentially vulnerable to resource exhaustion when parsing file data in forms. Applications using 'werkzeug.formparser.MultiPartParser' to parse 'multipart/form-data' requests (e.g. all flask applications) are vulnerable to a relatively simple but effective resource exhaustion (denial of service) attack. A specifically crafted form submission request can cause the parser to allocate and block 3 to 8 times the upload size in main memory. There is no upper limit; a single upload at 1 Gbit/s can exhaust 32 GB of RAM in less than 60 seconds.

Werkzeug 3.0.1 and 2.3.8 include a security fix: Slow multipart parsing for large parts potentially enabling DoS attacks.
https://github.com/pallets/werkzeug/commit/b1916c0c083e0be1c9d887ee2f3d696922bfc5c1

Werkzeug is a comprehensive WSGI web application library. If an upload of a file that starts with CR or LF and then is followed by megabytes of data without these characters: all of these bytes are appended chunk by chunk into internal bytearray and lookup for boundary is performed on growing buffer. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests.

Werkzeug 2.2.3 includes a fix for CVE-2023-23934: Browsers may allow "nameless" cookies that look like '=value' instead of 'key=value'. A vulnerable browser may allow a compromised application on an adjacent subdomain to exploit this to set a cookie like '=__Host-test=bad' for another subdomain. Werkzeug prior to 2.2.3 will parse the cookie '=__Host-test=bad' as __Host-test=bad'. If a Werkzeug application is running next to a vulnerable or malicious subdomain which sets such a cookie using a vulnerable browser, the Werkzeug application will see the bad cookie value but the valid cookie key.
https://github.com/pallets/werkzeug/security/advisories/GHSA-px8h-6qxv-m22q

Affected versions of Werkzeug are vulnerable to Path Traversal (CWE-22) on Windows systems running Python versions below 3.11. The safe_join() function failed to properly detect certain absolute paths on Windows, allowing attackers to potentially access files outside the intended directory. An attacker could craft special paths starting with "/" that bypass the directory restrictions on Windows systems. The vulnerability exists in the safe_join() function which relied solely on os.path.isabs() for path validation. This is exploitable on Windows systems by passing paths starting with "/" to safe_join(). To remediate, upgrade to the latest version which includes additional path validation checks. 
NOTE: This vulnerability specifically affects Windows systems running Python versions below 3.11 where ntpath.isabs() behavior differs.

Werkzeug is a comprehensive WSGI web application library. The debugger in affected versions of Werkzeug can allow an attacker to execute code on a developer's machine under some circumstances. This requires the attacker to get the developer to interact with a domain and subdomain they control, and enter the debugger PIN, but if they are successful it allows access to the debugger even if it is only running on localhost. This also requires the attacker to guess a URL in the developer's application that will trigger the debugger.

Sqlalchemy-utils from version 0.27.0 'EncryptedType' uses by default AES with CBC mode. The IV that it uses is not random though.
https://github.com/kvesteri/sqlalchemy-utils/issues/166
https://github.com/kvesteri/sqlalchemy-utils/pull/499

Lxml 4.9.1 includes a fix for CVE-2022-2309: NULL Pointer Dereference allows attackers to cause a denial of service (or application crash). This only applies when lxml is used together with libxml2 2.9.10 through 2.9.14. libxml2 2.9.9 and earlier are not affected. It allows triggering crashes through forged input data, given a vulnerable code sequence in the application. The vulnerability is caused by the iterwalk function (also used by the canonicalize function). Such code shouldn't be in wide-spread use, given that parsing + iterwalk would usually be replaced with the more efficient iterparse function. However, an XML converter that serialises to C14N would also be vulnerable, for example, and there are legitimate use cases for this code sequence. If untrusted input is received (also remotely) and processed via iterwalk function, a crash can be triggered.

Flask 2.2.5 and 2.3.2 include a fix for CVE-2023-30861: When all of the following conditions are met, a response containing data intended for one client may be cached and subsequently sent by the proxy to other clients. If the proxy also caches 'Set-Cookie' headers, it may send one client's 'session' cookie to other clients. The severity depends on the application's use of the session and the proxy's behavior regarding cookies. The risk depends on all these conditions being met:
1. The application must be hosted behind a caching proxy that does not strip cookies or ignore responses with cookies.
2. The application sets 'session.permanent = True'
3. The application does not access or modify the session at any point during a request.
4. 'SESSION_REFRESH_EACH_REQUEST' enabled (the default).
5. The application does not set a 'Cache-Control' header to indicate that a page is private or should not be cached.
This happens because vulnerable versions of Flask only set the 'Vary: Cookie' header when the session is accessed or modified, not when it is refreshed (re-sent to update the expiration) without being accessed or modified.
https://github.com/pallets/flask/security/advisories/GHSA-m2qf-hxjv-5gpq

Pillow 9.0.0 ensures JpegImagePlugin stops at the end of a truncated file to avoid Denial of Service attacks.
https://github.com/python-pillow/Pillow/pull/5921
https://github.com/advisories/GHSA-4fx9-vc88-q2xc

Pillow 10.0.1 updates its C dependency 'libwebp' to 1.3.2 to include a fix for a high-risk vulnerability.
https://pillow.readthedocs.io/en/stable/releasenotes/10.0.1.html

Pillow 9.0.0 excludes carriage return in PDF regex to help prevent ReDoS.
https://github.com/python-pillow/Pillow/pull/5912
https://github.com/python-pillow/Pillow/commit/43b800d933c996226e4d7df00c33fcbe46d97363

Pillow before 9.0.1 allows attackers to delete files because spaces in temporary pathnames are mishandled.

Pillow 9.0.0 includes a fix for CVE-2022-22815: path_getbbox in path.c in Pillow before 9.0.0 improperly initializes ImagePath.Path.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.0.html#fixed-imagepath-path-array-handling

Pillow 9.0.1 includes a fix for CVE-2022-22817: PIL.ImageMath.eval in Pillow before 9.0.0 allows evaluation of arbitrary expressions, such as ones that use the Python exec method. A first patch was issued for version 9.0.0 but it did not prevent builtins available to lambda expressions.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.1.html#security

Pillow 9.0.0 includes a fix for CVE-2022-22816: path_getbbox in path.c in Pillow before 9.0.0 has a buffer over-read during initialization of ImagePath.Path.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.0.html#fixed-imagepath-path-array-handling

Pillow 10.3.0 introduces a security update addressing CVE-2024-28219 by replacing certain functions with strncpy to prevent buffer overflow issues.

Pillow is affected by an arbitrary code execution vulnerability. If an attacker has control over the keys passed to the environment argument of PIL.ImageMath.eval(), they may be able to execute arbitrary code.
https://pillow.readthedocs.io/en/stable/releasenotes/10.2.0.html

Pillow 10.0.0 includes a fix for CVE-2023-44271: Denial of Service that uncontrollably allocates memory to process a given task, potentially causing a service to crash by having it run out of memory. This occurs for truetype in ImageFont when textlength in an ImageDraw instance operates on a long text argument.
https://github.com/python-pillow/Pillow/pull/7244

Pillow before 9.2.0 performs Improper Handling of Highly Compressed GIF Data (Data Amplification).

Pillow is potentially vulnerable to DoS attacks through PIL.ImageFont.ImageFont.getmask(). A decompression bomb check has also been added to the affected function.

When Tornado receives a request with two Transfer-Encoding: chunked headers, it ignores them both. This enables request smuggling when Tornado is deployed behind a proxy server that emits such requests. Pound does this.

Summary: Tornado's interpretation of symbols `-`, `+`, and `_` within chunk lengths and 'Content-Length' values contradicts the HTTP RFCs stipulations, potentially creating an avenue for request smuggling. This issue is generally found when Tornado operates behind specific proxies that understand these non-standard characters diversely, mostly observed in earlier versions of 'haproxy'; however, the latest version remains unaffected.

Details: Tornado utilizes the 'int' constructor to decipher the 'Content-Length' headers and chunk lengths in the locations mentioned below:

`tornado/http1connection.py:445`
Python3 code: self._expected_content_remaining = int(headers["Content-Length"])

`tornado/http1connection.py:621`
Python3 code: content_length = int(headers["Content-Length"])

`tornado/http1connection.py:671`
Python3 code: chunk_len = int(chunk_len_str.strip(), 16)

Notably, though the equation `int("0_0")` equates to `int("+0")`, `int("-0")`, and `int("0")`, using the 'int' constructor as a strategy for validating and parsing strings containing ASCII digits only is proven inadequate.

Tornado web framework affected versions contain a performance vulnerability in their HTTP cookie parser. When processing specially crafted malicious cookie headers, the parser's algorithm can exhibit quadratic time complexity. Since this parsing happens in the main event loop thread, it can cause the server to become unresponsive and block the processing of other incoming requests due to excessive CPU usage.

When Tornado's multipart/form-data parser encounters certain errors, it logs a warning but continues trying to parse the remainder of the data. This allows remote attackers to generate an extremely high volume of logs, constituting a DoS attack. This DoS is compounded by the fact that the logging subsystem is synchronous.

Tornado 6.3.2 includes a fix for CVE-2023-28370: Open redirect vulnerability in Tornado versions 6.3.1 and earlier allows a remote unauthenticated attacker to redirect a user to an arbitrary web site and conduct a phishing attack by having user access a specially crafted URL.

Tornado’s curl_httpclient.CurlAsyncHTTPClient class is vulnerable to CRLF (carriage return/line feed) injection in the request headers.

Hiredis (python wrapper for hiredis) 2.1.0 supports hiredis 1.1.0, that includes a security fix.
https://github.com/redis/hiredis-py/pull/135

An issue in Gevent before version 23.9.0 allows a remote attacker to escalate privileges via a crafted script to the WSGIServer component.

Affected versions of gevent are potentially vulnerable to a Race Condition leading to Unauthorized Access — CWE-362.

Affected versions of gevent were potentially vulnerable to HTTP request smuggling. The issue existed in the pywsgi Input._send_100_continue handling.

Affected versions of the Werkzeug package are vulnerable to Denial of Service (DoS) due to improper handling of Windows special device names in the safe_join function. In Werkzeug versions before 3.1.4, safe_join permits path segments such as “CON” or “AUX” to pass validation, allowing send_from_directory to construct a path that resolves to a Windows device file, which opens successfully but then blocks indefinitely when read.

Werkzeug 2.2.3 includes a fix for CVE-2023-25577: Prior to version 2.2.3, Werkzeug's multipart form data parser will parse an unlimited number of parts, including file parts. Parts can be a small amount of bytes, but each requires CPU time to parse and may use more memory as Python data. If a request can be made to an endpoint that accesses 'request.data', 'request.form', 'request.files', or 'request.get_data(parse_form_data=False)', it can cause unexpectedly high resource usage. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests. The amount of RAM required can trigger an out of memory kill of the process. Unlimited file parts can use up memory and file handles. If many concurrent requests are sent continuously, this can exhaust or kill all available workers.
https://github.com/pallets/werkzeug/security/advisories/GHSA-xg9f-g7g7-2323

Affected versions of Werkzeug are potentially vulnerable to resource exhaustion when parsing file data in forms. Applications using 'werkzeug.formparser.MultiPartParser' to parse 'multipart/form-data' requests (e.g. all flask applications) are vulnerable to a relatively simple but effective resource exhaustion (denial of service) attack. A specifically crafted form submission request can cause the parser to allocate and block 3 to 8 times the upload size in main memory. There is no upper limit; a single upload at 1 Gbit/s can exhaust 32 GB of RAM in less than 60 seconds.

Werkzeug 3.0.1 and 2.3.8 include a security fix: Slow multipart parsing for large parts potentially enabling DoS attacks.
https://github.com/pallets/werkzeug/commit/b1916c0c083e0be1c9d887ee2f3d696922bfc5c1

Werkzeug is a comprehensive WSGI web application library. If an upload of a file that starts with CR or LF and then is followed by megabytes of data without these characters: all of these bytes are appended chunk by chunk into internal bytearray and lookup for boundary is performed on growing buffer. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests.

Werkzeug 2.2.3 includes a fix for CVE-2023-23934: Browsers may allow "nameless" cookies that look like '=value' instead of 'key=value'. A vulnerable browser may allow a compromised application on an adjacent subdomain to exploit this to set a cookie like '=__Host-test=bad' for another subdomain. Werkzeug prior to 2.2.3 will parse the cookie '=__Host-test=bad' as __Host-test=bad'. If a Werkzeug application is running next to a vulnerable or malicious subdomain which sets such a cookie using a vulnerable browser, the Werkzeug application will see the bad cookie value but the valid cookie key.
https://github.com/pallets/werkzeug/security/advisories/GHSA-px8h-6qxv-m22q

Affected versions of Werkzeug are vulnerable to Path Traversal (CWE-22) on Windows systems running Python versions below 3.11. The safe_join() function failed to properly detect certain absolute paths on Windows, allowing attackers to potentially access files outside the intended directory. An attacker could craft special paths starting with "/" that bypass the directory restrictions on Windows systems. The vulnerability exists in the safe_join() function which relied solely on os.path.isabs() for path validation. This is exploitable on Windows systems by passing paths starting with "/" to safe_join(). To remediate, upgrade to the latest version which includes additional path validation checks. 
NOTE: This vulnerability specifically affects Windows systems running Python versions below 3.11 where ntpath.isabs() behavior differs.

Werkzeug is a comprehensive WSGI web application library. The debugger in affected versions of Werkzeug can allow an attacker to execute code on a developer's machine under some circumstances. This requires the attacker to get the developer to interact with a domain and subdomain they control, and enter the debugger PIN, but if they are successful it allows access to the debugger even if it is only running on localhost. This also requires the attacker to guess a URL in the developer's application that will trigger the debugger.

Sqlalchemy-utils from version 0.27.0 'EncryptedType' uses by default AES with CBC mode. The IV that it uses is not random though.
https://github.com/kvesteri/sqlalchemy-utils/issues/166
https://github.com/kvesteri/sqlalchemy-utils/pull/499

Sqlalchemy-utils from version 0.27.0 'EncryptedType' uses by default AES with CBC mode. The IV that it uses is not random though.
https://github.com/kvesteri/sqlalchemy-utils/issues/166
https://github.com/kvesteri/sqlalchemy-utils/pull/499

Lxml 4.9.1 includes a fix for CVE-2022-2309: NULL Pointer Dereference allows attackers to cause a denial of service (or application crash). This only applies when lxml is used together with libxml2 2.9.10 through 2.9.14. libxml2 2.9.9 and earlier are not affected. It allows triggering crashes through forged input data, given a vulnerable code sequence in the application. The vulnerability is caused by the iterwalk function (also used by the canonicalize function). Such code shouldn't be in wide-spread use, given that parsing + iterwalk would usually be replaced with the more efficient iterparse function. However, an XML converter that serialises to C14N would also be vulnerable, for example, and there are legitimate use cases for this code sequence. If untrusted input is received (also remotely) and processed via iterwalk function, a crash can be triggered.

Flask 2.2.5 and 2.3.2 include a fix for CVE-2023-30861: When all of the following conditions are met, a response containing data intended for one client may be cached and subsequently sent by the proxy to other clients. If the proxy also caches 'Set-Cookie' headers, it may send one client's 'session' cookie to other clients. The severity depends on the application's use of the session and the proxy's behavior regarding cookies. The risk depends on all these conditions being met:
1. The application must be hosted behind a caching proxy that does not strip cookies or ignore responses with cookies.
2. The application sets 'session.permanent = True'
3. The application does not access or modify the session at any point during a request.
4. 'SESSION_REFRESH_EACH_REQUEST' enabled (the default).
5. The application does not set a 'Cache-Control' header to indicate that a page is private or should not be cached.
This happens because vulnerable versions of Flask only set the 'Vary: Cookie' header when the session is accessed or modified, not when it is refreshed (re-sent to update the expiration) without being accessed or modified.
https://github.com/pallets/flask/security/advisories/GHSA-m2qf-hxjv-5gpq

Pillow 9.0.0 ensures JpegImagePlugin stops at the end of a truncated file to avoid Denial of Service attacks.
https://github.com/python-pillow/Pillow/pull/5921
https://github.com/advisories/GHSA-4fx9-vc88-q2xc

Pillow 10.0.1 updates its C dependency 'libwebp' to 1.3.2 to include a fix for a high-risk vulnerability.
https://pillow.readthedocs.io/en/stable/releasenotes/10.0.1.html

Pillow 9.0.0 excludes carriage return in PDF regex to help prevent ReDoS.
https://github.com/python-pillow/Pillow/pull/5912
https://github.com/python-pillow/Pillow/commit/43b800d933c996226e4d7df00c33fcbe46d97363

Pillow before 9.0.1 allows attackers to delete files because spaces in temporary pathnames are mishandled.

Pillow 9.0.0 includes a fix for CVE-2022-22815: path_getbbox in path.c in Pillow before 9.0.0 improperly initializes ImagePath.Path.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.0.html#fixed-imagepath-path-array-handling

Pillow 9.0.1 includes a fix for CVE-2022-22817: PIL.ImageMath.eval in Pillow before 9.0.0 allows evaluation of arbitrary expressions, such as ones that use the Python exec method. A first patch was issued for version 9.0.0 but it did not prevent builtins available to lambda expressions.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.1.html#security

Pillow 9.0.0 includes a fix for CVE-2022-22816: path_getbbox in path.c in Pillow before 9.0.0 has a buffer over-read during initialization of ImagePath.Path.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.0.html#fixed-imagepath-path-array-handling

Pillow 10.3.0 introduces a security update addressing CVE-2024-28219 by replacing certain functions with strncpy to prevent buffer overflow issues.

Pillow is affected by an arbitrary code execution vulnerability. If an attacker has control over the keys passed to the environment argument of PIL.ImageMath.eval(), they may be able to execute arbitrary code.
https://pillow.readthedocs.io/en/stable/releasenotes/10.2.0.html

Pillow 10.0.0 includes a fix for CVE-2023-44271: Denial of Service that uncontrollably allocates memory to process a given task, potentially causing a service to crash by having it run out of memory. This occurs for truetype in ImageFont when textlength in an ImageDraw instance operates on a long text argument.
https://github.com/python-pillow/Pillow/pull/7244

Pillow before 9.2.0 performs Improper Handling of Highly Compressed GIF Data (Data Amplification).

Pillow is potentially vulnerable to DoS attacks through PIL.ImageFont.ImageFont.getmask(). A decompression bomb check has also been added to the affected function.

When Tornado receives a request with two Transfer-Encoding: chunked headers, it ignores them both. This enables request smuggling when Tornado is deployed behind a proxy server that emits such requests. Pound does this.

Summary: Tornado's interpretation of symbols `-`, `+`, and `_` within chunk lengths and 'Content-Length' values contradicts the HTTP RFCs stipulations, potentially creating an avenue for request smuggling. This issue is generally found when Tornado operates behind specific proxies that understand these non-standard characters diversely, mostly observed in earlier versions of 'haproxy'; however, the latest version remains unaffected.

Details: Tornado utilizes the 'int' constructor to decipher the 'Content-Length' headers and chunk lengths in the locations mentioned below:

`tornado/http1connection.py:445`
Python3 code: self._expected_content_remaining = int(headers["Content-Length"])

`tornado/http1connection.py:621`
Python3 code: content_length = int(headers["Content-Length"])

`tornado/http1connection.py:671`
Python3 code: chunk_len = int(chunk_len_str.strip(), 16)

Notably, though the equation `int("0_0")` equates to `int("+0")`, `int("-0")`, and `int("0")`, using the 'int' constructor as a strategy for validating and parsing strings containing ASCII digits only is proven inadequate.

Tornado web framework affected versions contain a performance vulnerability in their HTTP cookie parser. When processing specially crafted malicious cookie headers, the parser's algorithm can exhibit quadratic time complexity. Since this parsing happens in the main event loop thread, it can cause the server to become unresponsive and block the processing of other incoming requests due to excessive CPU usage.

When Tornado's multipart/form-data parser encounters certain errors, it logs a warning but continues trying to parse the remainder of the data. This allows remote attackers to generate an extremely high volume of logs, constituting a DoS attack. This DoS is compounded by the fact that the logging subsystem is synchronous.

Tornado 6.3.2 includes a fix for CVE-2023-28370: Open redirect vulnerability in Tornado versions 6.3.1 and earlier allows a remote unauthenticated attacker to redirect a user to an arbitrary web site and conduct a phishing attack by having user access a specially crafted URL.

Tornado’s curl_httpclient.CurlAsyncHTTPClient class is vulnerable to CRLF (carriage return/line feed) injection in the request headers.

Hiredis (python wrapper for hiredis) 2.1.0 supports hiredis 1.1.0, that includes a security fix.
https://github.com/redis/hiredis-py/pull/135

An issue in Gevent before version 23.9.0 allows a remote attacker to escalate privileges via a crafted script to the WSGIServer component.

Affected versions of gevent are potentially vulnerable to a Race Condition leading to Unauthorized Access — CWE-362.

Affected versions of gevent were potentially vulnerable to HTTP request smuggling. The issue existed in the pywsgi Input._send_100_continue handling.

Affected versions of the Werkzeug package are vulnerable to Denial of Service (DoS) due to improper handling of Windows special device names in the safe_join function. In Werkzeug versions before 3.1.4, safe_join permits path segments such as “CON” or “AUX” to pass validation, allowing send_from_directory to construct a path that resolves to a Windows device file, which opens successfully but then blocks indefinitely when read.

Werkzeug 2.2.3 includes a fix for CVE-2023-25577: Prior to version 2.2.3, Werkzeug's multipart form data parser will parse an unlimited number of parts, including file parts. Parts can be a small amount of bytes, but each requires CPU time to parse and may use more memory as Python data. If a request can be made to an endpoint that accesses 'request.data', 'request.form', 'request.files', or 'request.get_data(parse_form_data=False)', it can cause unexpectedly high resource usage. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests. The amount of RAM required can trigger an out of memory kill of the process. Unlimited file parts can use up memory and file handles. If many concurrent requests are sent continuously, this can exhaust or kill all available workers.
https://github.com/pallets/werkzeug/security/advisories/GHSA-xg9f-g7g7-2323

Affected versions of Werkzeug are potentially vulnerable to resource exhaustion when parsing file data in forms. Applications using 'werkzeug.formparser.MultiPartParser' to parse 'multipart/form-data' requests (e.g. all flask applications) are vulnerable to a relatively simple but effective resource exhaustion (denial of service) attack. A specifically crafted form submission request can cause the parser to allocate and block 3 to 8 times the upload size in main memory. There is no upper limit; a single upload at 1 Gbit/s can exhaust 32 GB of RAM in less than 60 seconds.

Werkzeug 3.0.1 and 2.3.8 include a security fix: Slow multipart parsing for large parts potentially enabling DoS attacks.
https://github.com/pallets/werkzeug/commit/b1916c0c083e0be1c9d887ee2f3d696922bfc5c1

Werkzeug is a comprehensive WSGI web application library. If an upload of a file that starts with CR or LF and then is followed by megabytes of data without these characters: all of these bytes are appended chunk by chunk into internal bytearray and lookup for boundary is performed on growing buffer. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests.

Werkzeug 2.2.3 includes a fix for CVE-2023-23934: Browsers may allow "nameless" cookies that look like '=value' instead of 'key=value'. A vulnerable browser may allow a compromised application on an adjacent subdomain to exploit this to set a cookie like '=__Host-test=bad' for another subdomain. Werkzeug prior to 2.2.3 will parse the cookie '=__Host-test=bad' as __Host-test=bad'. If a Werkzeug application is running next to a vulnerable or malicious subdomain which sets such a cookie using a vulnerable browser, the Werkzeug application will see the bad cookie value but the valid cookie key.
https://github.com/pallets/werkzeug/security/advisories/GHSA-px8h-6qxv-m22q

Affected versions of Werkzeug are vulnerable to Path Traversal (CWE-22) on Windows systems running Python versions below 3.11. The safe_join() function failed to properly detect certain absolute paths on Windows, allowing attackers to potentially access files outside the intended directory. An attacker could craft special paths starting with "/" that bypass the directory restrictions on Windows systems. The vulnerability exists in the safe_join() function which relied solely on os.path.isabs() for path validation. This is exploitable on Windows systems by passing paths starting with "/" to safe_join(). To remediate, upgrade to the latest version which includes additional path validation checks. 
NOTE: This vulnerability specifically affects Windows systems running Python versions below 3.11 where ntpath.isabs() behavior differs.

Werkzeug is a comprehensive WSGI web application library. The debugger in affected versions of Werkzeug can allow an attacker to execute code on a developer's machine under some circumstances. This requires the attacker to get the developer to interact with a domain and subdomain they control, and enter the debugger PIN, but if they are successful it allows access to the debugger even if it is only running on localhost. This also requires the attacker to guess a URL in the developer's application that will trigger the debugger.

Sqlalchemy-utils from version 0.27.0 'EncryptedType' uses by default AES with CBC mode. The IV that it uses is not random though.
https://github.com/kvesteri/sqlalchemy-utils/issues/166
https://github.com/kvesteri/sqlalchemy-utils/pull/499

Affected versions of the Werkzeug package are vulnerable to Denial of Service (DoS) due to improper handling of Windows special device names in the safe_join function. In Werkzeug versions before 3.1.4, safe_join permits path segments such as “CON” or “AUX” to pass validation, allowing send_from_directory to construct a path that resolves to a Windows device file, which opens successfully but then blocks indefinitely when read.

Werkzeug 2.2.3 includes a fix for CVE-2023-25577: Prior to version 2.2.3, Werkzeug's multipart form data parser will parse an unlimited number of parts, including file parts. Parts can be a small amount of bytes, but each requires CPU time to parse and may use more memory as Python data. If a request can be made to an endpoint that accesses 'request.data', 'request.form', 'request.files', or 'request.get_data(parse_form_data=False)', it can cause unexpectedly high resource usage. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests. The amount of RAM required can trigger an out of memory kill of the process. Unlimited file parts can use up memory and file handles. If many concurrent requests are sent continuously, this can exhaust or kill all available workers.
https://github.com/pallets/werkzeug/security/advisories/GHSA-xg9f-g7g7-2323

Affected versions of Werkzeug are potentially vulnerable to resource exhaustion when parsing file data in forms. Applications using 'werkzeug.formparser.MultiPartParser' to parse 'multipart/form-data' requests (e.g. all flask applications) are vulnerable to a relatively simple but effective resource exhaustion (denial of service) attack. A specifically crafted form submission request can cause the parser to allocate and block 3 to 8 times the upload size in main memory. There is no upper limit; a single upload at 1 Gbit/s can exhaust 32 GB of RAM in less than 60 seconds.

Werkzeug 3.0.1 and 2.3.8 include a security fix: Slow multipart parsing for large parts potentially enabling DoS attacks.
https://github.com/pallets/werkzeug/commit/b1916c0c083e0be1c9d887ee2f3d696922bfc5c1

Werkzeug is a comprehensive WSGI web application library. If an upload of a file that starts with CR or LF and then is followed by megabytes of data without these characters: all of these bytes are appended chunk by chunk into internal bytearray and lookup for boundary is performed on growing buffer. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests.

Werkzeug 2.2.3 includes a fix for CVE-2023-23934: Browsers may allow "nameless" cookies that look like '=value' instead of 'key=value'. A vulnerable browser may allow a compromised application on an adjacent subdomain to exploit this to set a cookie like '=__Host-test=bad' for another subdomain. Werkzeug prior to 2.2.3 will parse the cookie '=__Host-test=bad' as __Host-test=bad'. If a Werkzeug application is running next to a vulnerable or malicious subdomain which sets such a cookie using a vulnerable browser, the Werkzeug application will see the bad cookie value but the valid cookie key.
https://github.com/pallets/werkzeug/security/advisories/GHSA-px8h-6qxv-m22q

Affected versions of Werkzeug are vulnerable to Path Traversal (CWE-22) on Windows systems running Python versions below 3.11. The safe_join() function failed to properly detect certain absolute paths on Windows, allowing attackers to potentially access files outside the intended directory. An attacker could craft special paths starting with "/" that bypass the directory restrictions on Windows systems. The vulnerability exists in the safe_join() function which relied solely on os.path.isabs() for path validation. This is exploitable on Windows systems by passing paths starting with "/" to safe_join(). To remediate, upgrade to the latest version which includes additional path validation checks. 
NOTE: This vulnerability specifically affects Windows systems running Python versions below 3.11 where ntpath.isabs() behavior differs.

Werkzeug is a comprehensive WSGI web application library. The debugger in affected versions of Werkzeug can allow an attacker to execute code on a developer's machine under some circumstances. This requires the attacker to get the developer to interact with a domain and subdomain they control, and enter the debugger PIN, but if they are successful it allows access to the debugger even if it is only running on localhost. This also requires the attacker to guess a URL in the developer's application that will trigger the debugger.

Sqlalchemy-utils from version 0.27.0 'EncryptedType' uses by default AES with CBC mode. The IV that it uses is not random though.
https://github.com/kvesteri/sqlalchemy-utils/issues/166
https://github.com/kvesteri/sqlalchemy-utils/pull/499

Lxml 4.9.1 includes a fix for CVE-2022-2309: NULL Pointer Dereference allows attackers to cause a denial of service (or application crash). This only applies when lxml is used together with libxml2 2.9.10 through 2.9.14. libxml2 2.9.9 and earlier are not affected. It allows triggering crashes through forged input data, given a vulnerable code sequence in the application. The vulnerability is caused by the iterwalk function (also used by the canonicalize function). Such code shouldn't be in wide-spread use, given that parsing + iterwalk would usually be replaced with the more efficient iterparse function. However, an XML converter that serialises to C14N would also be vulnerable, for example, and there are legitimate use cases for this code sequence. If untrusted input is received (also remotely) and processed via iterwalk function, a crash can be triggered.

Flask 2.2.5 and 2.3.2 include a fix for CVE-2023-30861: When all of the following conditions are met, a response containing data intended for one client may be cached and subsequently sent by the proxy to other clients. If the proxy also caches 'Set-Cookie' headers, it may send one client's 'session' cookie to other clients. The severity depends on the application's use of the session and the proxy's behavior regarding cookies. The risk depends on all these conditions being met:
1. The application must be hosted behind a caching proxy that does not strip cookies or ignore responses with cookies.
2. The application sets 'session.permanent = True'
3. The application does not access or modify the session at any point during a request.
4. 'SESSION_REFRESH_EACH_REQUEST' enabled (the default).
5. The application does not set a 'Cache-Control' header to indicate that a page is private or should not be cached.
This happens because vulnerable versions of Flask only set the 'Vary: Cookie' header when the session is accessed or modified, not when it is refreshed (re-sent to update the expiration) without being accessed or modified.
https://github.com/pallets/flask/security/advisories/GHSA-m2qf-hxjv-5gpq

Pillow 9.0.0 ensures JpegImagePlugin stops at the end of a truncated file to avoid Denial of Service attacks.
https://github.com/python-pillow/Pillow/pull/5921
https://github.com/advisories/GHSA-4fx9-vc88-q2xc

Pillow 10.0.1 updates its C dependency 'libwebp' to 1.3.2 to include a fix for a high-risk vulnerability.
https://pillow.readthedocs.io/en/stable/releasenotes/10.0.1.html

Pillow 9.0.0 excludes carriage return in PDF regex to help prevent ReDoS.
https://github.com/python-pillow/Pillow/pull/5912
https://github.com/python-pillow/Pillow/commit/43b800d933c996226e4d7df00c33fcbe46d97363

Pillow before 9.0.1 allows attackers to delete files because spaces in temporary pathnames are mishandled.

Pillow 9.0.0 includes a fix for CVE-2022-22815: path_getbbox in path.c in Pillow before 9.0.0 improperly initializes ImagePath.Path.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.0.html#fixed-imagepath-path-array-handling

Pillow 9.0.1 includes a fix for CVE-2022-22817: PIL.ImageMath.eval in Pillow before 9.0.0 allows evaluation of arbitrary expressions, such as ones that use the Python exec method. A first patch was issued for version 9.0.0 but it did not prevent builtins available to lambda expressions.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.1.html#security

Pillow 9.0.0 includes a fix for CVE-2022-22816: path_getbbox in path.c in Pillow before 9.0.0 has a buffer over-read during initialization of ImagePath.Path.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.0.html#fixed-imagepath-path-array-handling

Pillow 10.3.0 introduces a security update addressing CVE-2024-28219 by replacing certain functions with strncpy to prevent buffer overflow issues.

Pillow is affected by an arbitrary code execution vulnerability. If an attacker has control over the keys passed to the environment argument of PIL.ImageMath.eval(), they may be able to execute arbitrary code.
https://pillow.readthedocs.io/en/stable/releasenotes/10.2.0.html

Pillow 10.0.0 includes a fix for CVE-2023-44271: Denial of Service that uncontrollably allocates memory to process a given task, potentially causing a service to crash by having it run out of memory. This occurs for truetype in ImageFont when textlength in an ImageDraw instance operates on a long text argument.
https://github.com/python-pillow/Pillow/pull/7244

Pillow before 9.2.0 performs Improper Handling of Highly Compressed GIF Data (Data Amplification).

Pillow is potentially vulnerable to DoS attacks through PIL.ImageFont.ImageFont.getmask(). A decompression bomb check has also been added to the affected function.

When Tornado receives a request with two Transfer-Encoding: chunked headers, it ignores them both. This enables request smuggling when Tornado is deployed behind a proxy server that emits such requests. Pound does this.

Summary: Tornado's interpretation of symbols `-`, `+`, and `_` within chunk lengths and 'Content-Length' values contradicts the HTTP RFCs stipulations, potentially creating an avenue for request smuggling. This issue is generally found when Tornado operates behind specific proxies that understand these non-standard characters diversely, mostly observed in earlier versions of 'haproxy'; however, the latest version remains unaffected.

Details: Tornado utilizes the 'int' constructor to decipher the 'Content-Length' headers and chunk lengths in the locations mentioned below:

`tornado/http1connection.py:445`
Python3 code: self._expected_content_remaining = int(headers["Content-Length"])

`tornado/http1connection.py:621`
Python3 code: content_length = int(headers["Content-Length"])

`tornado/http1connection.py:671`
Python3 code: chunk_len = int(chunk_len_str.strip(), 16)

Notably, though the equation `int("0_0")` equates to `int("+0")`, `int("-0")`, and `int("0")`, using the 'int' constructor as a strategy for validating and parsing strings containing ASCII digits only is proven inadequate.

Tornado web framework affected versions contain a performance vulnerability in their HTTP cookie parser. When processing specially crafted malicious cookie headers, the parser's algorithm can exhibit quadratic time complexity. Since this parsing happens in the main event loop thread, it can cause the server to become unresponsive and block the processing of other incoming requests due to excessive CPU usage.

When Tornado's multipart/form-data parser encounters certain errors, it logs a warning but continues trying to parse the remainder of the data. This allows remote attackers to generate an extremely high volume of logs, constituting a DoS attack. This DoS is compounded by the fact that the logging subsystem is synchronous.

Tornado 6.3.2 includes a fix for CVE-2023-28370: Open redirect vulnerability in Tornado versions 6.3.1 and earlier allows a remote unauthenticated attacker to redirect a user to an arbitrary web site and conduct a phishing attack by having user access a specially crafted URL.

Tornado’s curl_httpclient.CurlAsyncHTTPClient class is vulnerable to CRLF (carriage return/line feed) injection in the request headers.

Hiredis (python wrapper for hiredis) 2.1.0 supports hiredis 1.1.0, that includes a security fix.
https://github.com/redis/hiredis-py/pull/135

An issue in Gevent before version 23.9.0 allows a remote attacker to escalate privileges via a crafted script to the WSGIServer component.

Affected versions of gevent are potentially vulnerable to a Race Condition leading to Unauthorized Access — CWE-362.

Affected versions of gevent were potentially vulnerable to HTTP request smuggling. The issue existed in the pywsgi Input._send_100_continue handling.

Affected versions of the Werkzeug package are vulnerable to Denial of Service (DoS) due to improper handling of Windows special device names in the safe_join function. In Werkzeug versions before 3.1.4, safe_join permits path segments such as “CON” or “AUX” to pass validation, allowing send_from_directory to construct a path that resolves to a Windows device file, which opens successfully but then blocks indefinitely when read.

Werkzeug 2.2.3 includes a fix for CVE-2023-25577: Prior to version 2.2.3, Werkzeug's multipart form data parser will parse an unlimited number of parts, including file parts. Parts can be a small amount of bytes, but each requires CPU time to parse and may use more memory as Python data. If a request can be made to an endpoint that accesses 'request.data', 'request.form', 'request.files', or 'request.get_data(parse_form_data=False)', it can cause unexpectedly high resource usage. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests. The amount of RAM required can trigger an out of memory kill of the process. Unlimited file parts can use up memory and file handles. If many concurrent requests are sent continuously, this can exhaust or kill all available workers.
https://github.com/pallets/werkzeug/security/advisories/GHSA-xg9f-g7g7-2323

Affected versions of Werkzeug are potentially vulnerable to resource exhaustion when parsing file data in forms. Applications using 'werkzeug.formparser.MultiPartParser' to parse 'multipart/form-data' requests (e.g. all flask applications) are vulnerable to a relatively simple but effective resource exhaustion (denial of service) attack. A specifically crafted form submission request can cause the parser to allocate and block 3 to 8 times the upload size in main memory. There is no upper limit; a single upload at 1 Gbit/s can exhaust 32 GB of RAM in less than 60 seconds.

Werkzeug 3.0.1 and 2.3.8 include a security fix: Slow multipart parsing for large parts potentially enabling DoS attacks.
https://github.com/pallets/werkzeug/commit/b1916c0c083e0be1c9d887ee2f3d696922bfc5c1

Werkzeug is a comprehensive WSGI web application library. If an upload of a file that starts with CR or LF and then is followed by megabytes of data without these characters: all of these bytes are appended chunk by chunk into internal bytearray and lookup for boundary is performed on growing buffer. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests.

Werkzeug 2.2.3 includes a fix for CVE-2023-23934: Browsers may allow "nameless" cookies that look like '=value' instead of 'key=value'. A vulnerable browser may allow a compromised application on an adjacent subdomain to exploit this to set a cookie like '=__Host-test=bad' for another subdomain. Werkzeug prior to 2.2.3 will parse the cookie '=__Host-test=bad' as __Host-test=bad'. If a Werkzeug application is running next to a vulnerable or malicious subdomain which sets such a cookie using a vulnerable browser, the Werkzeug application will see the bad cookie value but the valid cookie key.
https://github.com/pallets/werkzeug/security/advisories/GHSA-px8h-6qxv-m22q

Affected versions of Werkzeug are vulnerable to Path Traversal (CWE-22) on Windows systems running Python versions below 3.11. The safe_join() function failed to properly detect certain absolute paths on Windows, allowing attackers to potentially access files outside the intended directory. An attacker could craft special paths starting with "/" that bypass the directory restrictions on Windows systems. The vulnerability exists in the safe_join() function which relied solely on os.path.isabs() for path validation. This is exploitable on Windows systems by passing paths starting with "/" to safe_join(). To remediate, upgrade to the latest version which includes additional path validation checks. 
NOTE: This vulnerability specifically affects Windows systems running Python versions below 3.11 where ntpath.isabs() behavior differs.

Werkzeug is a comprehensive WSGI web application library. The debugger in affected versions of Werkzeug can allow an attacker to execute code on a developer's machine under some circumstances. This requires the attacker to get the developer to interact with a domain and subdomain they control, and enter the debugger PIN, but if they are successful it allows access to the debugger even if it is only running on localhost. This also requires the attacker to guess a URL in the developer's application that will trigger the debugger.

Sqlalchemy-utils from version 0.27.0 'EncryptedType' uses by default AES with CBC mode. The IV that it uses is not random though.
https://github.com/kvesteri/sqlalchemy-utils/issues/166
https://github.com/kvesteri/sqlalchemy-utils/pull/499

Affected versions of the Werkzeug package are vulnerable to Denial of Service (DoS) due to improper handling of Windows special device names in the safe_join function. In Werkzeug versions before 3.1.4, safe_join permits path segments such as “CON” or “AUX” to pass validation, allowing send_from_directory to construct a path that resolves to a Windows device file, which opens successfully but then blocks indefinitely when read.

Werkzeug 2.2.3 includes a fix for CVE-2023-25577: Prior to version 2.2.3, Werkzeug's multipart form data parser will parse an unlimited number of parts, including file parts. Parts can be a small amount of bytes, but each requires CPU time to parse and may use more memory as Python data. If a request can be made to an endpoint that accesses 'request.data', 'request.form', 'request.files', or 'request.get_data(parse_form_data=False)', it can cause unexpectedly high resource usage. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests. The amount of RAM required can trigger an out of memory kill of the process. Unlimited file parts can use up memory and file handles. If many concurrent requests are sent continuously, this can exhaust or kill all available workers.
https://github.com/pallets/werkzeug/security/advisories/GHSA-xg9f-g7g7-2323

Affected versions of Werkzeug are potentially vulnerable to resource exhaustion when parsing file data in forms. Applications using 'werkzeug.formparser.MultiPartParser' to parse 'multipart/form-data' requests (e.g. all flask applications) are vulnerable to a relatively simple but effective resource exhaustion (denial of service) attack. A specifically crafted form submission request can cause the parser to allocate and block 3 to 8 times the upload size in main memory. There is no upper limit; a single upload at 1 Gbit/s can exhaust 32 GB of RAM in less than 60 seconds.

Werkzeug 3.0.1 and 2.3.8 include a security fix: Slow multipart parsing for large parts potentially enabling DoS attacks.
https://github.com/pallets/werkzeug/commit/b1916c0c083e0be1c9d887ee2f3d696922bfc5c1

Werkzeug is a comprehensive WSGI web application library. If an upload of a file that starts with CR or LF and then is followed by megabytes of data without these characters: all of these bytes are appended chunk by chunk into internal bytearray and lookup for boundary is performed on growing buffer. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests.

Werkzeug 2.2.3 includes a fix for CVE-2023-23934: Browsers may allow "nameless" cookies that look like '=value' instead of 'key=value'. A vulnerable browser may allow a compromised application on an adjacent subdomain to exploit this to set a cookie like '=__Host-test=bad' for another subdomain. Werkzeug prior to 2.2.3 will parse the cookie '=__Host-test=bad' as __Host-test=bad'. If a Werkzeug application is running next to a vulnerable or malicious subdomain which sets such a cookie using a vulnerable browser, the Werkzeug application will see the bad cookie value but the valid cookie key.
https://github.com/pallets/werkzeug/security/advisories/GHSA-px8h-6qxv-m22q

Affected versions of Werkzeug are vulnerable to Path Traversal (CWE-22) on Windows systems running Python versions below 3.11. The safe_join() function failed to properly detect certain absolute paths on Windows, allowing attackers to potentially access files outside the intended directory. An attacker could craft special paths starting with "/" that bypass the directory restrictions on Windows systems. The vulnerability exists in the safe_join() function which relied solely on os.path.isabs() for path validation. This is exploitable on Windows systems by passing paths starting with "/" to safe_join(). To remediate, upgrade to the latest version which includes additional path validation checks. 
NOTE: This vulnerability specifically affects Windows systems running Python versions below 3.11 where ntpath.isabs() behavior differs.

Werkzeug is a comprehensive WSGI web application library. The debugger in affected versions of Werkzeug can allow an attacker to execute code on a developer's machine under some circumstances. This requires the attacker to get the developer to interact with a domain and subdomain they control, and enter the debugger PIN, but if they are successful it allows access to the debugger even if it is only running on localhost. This also requires the attacker to guess a URL in the developer's application that will trigger the debugger.

Sqlalchemy-utils from version 0.27.0 'EncryptedType' uses by default AES with CBC mode. The IV that it uses is not random though.
https://github.com/kvesteri/sqlalchemy-utils/issues/166
https://github.com/kvesteri/sqlalchemy-utils/pull/499

Lxml 4.9.1 includes a fix for CVE-2022-2309: NULL Pointer Dereference allows attackers to cause a denial of service (or application crash). This only applies when lxml is used together with libxml2 2.9.10 through 2.9.14. libxml2 2.9.9 and earlier are not affected. It allows triggering crashes through forged input data, given a vulnerable code sequence in the application. The vulnerability is caused by the iterwalk function (also used by the canonicalize function). Such code shouldn't be in wide-spread use, given that parsing + iterwalk would usually be replaced with the more efficient iterparse function. However, an XML converter that serialises to C14N would also be vulnerable, for example, and there are legitimate use cases for this code sequence. If untrusted input is received (also remotely) and processed via iterwalk function, a crash can be triggered.

Flask 2.2.5 and 2.3.2 include a fix for CVE-2023-30861: When all of the following conditions are met, a response containing data intended for one client may be cached and subsequently sent by the proxy to other clients. If the proxy also caches 'Set-Cookie' headers, it may send one client's 'session' cookie to other clients. The severity depends on the application's use of the session and the proxy's behavior regarding cookies. The risk depends on all these conditions being met:
1. The application must be hosted behind a caching proxy that does not strip cookies or ignore responses with cookies.
2. The application sets 'session.permanent = True'
3. The application does not access or modify the session at any point during a request.
4. 'SESSION_REFRESH_EACH_REQUEST' enabled (the default).
5. The application does not set a 'Cache-Control' header to indicate that a page is private or should not be cached.
This happens because vulnerable versions of Flask only set the 'Vary: Cookie' header when the session is accessed or modified, not when it is refreshed (re-sent to update the expiration) without being accessed or modified.
https://github.com/pallets/flask/security/advisories/GHSA-m2qf-hxjv-5gpq

Pillow 9.0.0 ensures JpegImagePlugin stops at the end of a truncated file to avoid Denial of Service attacks.
https://github.com/python-pillow/Pillow/pull/5921
https://github.com/advisories/GHSA-4fx9-vc88-q2xc

Pillow 10.0.1 updates its C dependency 'libwebp' to 1.3.2 to include a fix for a high-risk vulnerability.
https://pillow.readthedocs.io/en/stable/releasenotes/10.0.1.html

Pillow 9.0.0 excludes carriage return in PDF regex to help prevent ReDoS.
https://github.com/python-pillow/Pillow/pull/5912
https://github.com/python-pillow/Pillow/commit/43b800d933c996226e4d7df00c33fcbe46d97363

Pillow before 9.0.1 allows attackers to delete files because spaces in temporary pathnames are mishandled.

Pillow 9.0.0 includes a fix for CVE-2022-22815: path_getbbox in path.c in Pillow before 9.0.0 improperly initializes ImagePath.Path.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.0.html#fixed-imagepath-path-array-handling

Pillow 9.0.1 includes a fix for CVE-2022-22817: PIL.ImageMath.eval in Pillow before 9.0.0 allows evaluation of arbitrary expressions, such as ones that use the Python exec method. A first patch was issued for version 9.0.0 but it did not prevent builtins available to lambda expressions.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.1.html#security

Pillow 9.0.0 includes a fix for CVE-2022-22816: path_getbbox in path.c in Pillow before 9.0.0 has a buffer over-read during initialization of ImagePath.Path.
https://pillow.readthedocs.io/en/stable/releasenotes/9.0.0.html#fixed-imagepath-path-array-handling

Pillow 10.3.0 introduces a security update addressing CVE-2024-28219 by replacing certain functions with strncpy to prevent buffer overflow issues.

Pillow is affected by an arbitrary code execution vulnerability. If an attacker has control over the keys passed to the environment argument of PIL.ImageMath.eval(), they may be able to execute arbitrary code.
https://pillow.readthedocs.io/en/stable/releasenotes/10.2.0.html

Pillow 10.0.0 includes a fix for CVE-2023-44271: Denial of Service that uncontrollably allocates memory to process a given task, potentially causing a service to crash by having it run out of memory. This occurs for truetype in ImageFont when textlength in an ImageDraw instance operates on a long text argument.
https://github.com/python-pillow/Pillow/pull/7244

Pillow before 9.2.0 performs Improper Handling of Highly Compressed GIF Data (Data Amplification).

Pillow is potentially vulnerable to DoS attacks through PIL.ImageFont.ImageFont.getmask(). A decompression bomb check has also been added to the affected function.

When Tornado receives a request with two Transfer-Encoding: chunked headers, it ignores them both. This enables request smuggling when Tornado is deployed behind a proxy server that emits such requests. Pound does this.

Summary: Tornado's interpretation of symbols `-`, `+`, and `_` within chunk lengths and 'Content-Length' values contradicts the HTTP RFCs stipulations, potentially creating an avenue for request smuggling. This issue is generally found when Tornado operates behind specific proxies that understand these non-standard characters diversely, mostly observed in earlier versions of 'haproxy'; however, the latest version remains unaffected.

Details: Tornado utilizes the 'int' constructor to decipher the 'Content-Length' headers and chunk lengths in the locations mentioned below:

`tornado/http1connection.py:445`
Python3 code: self._expected_content_remaining = int(headers["Content-Length"])

`tornado/http1connection.py:621`
Python3 code: content_length = int(headers["Content-Length"])

`tornado/http1connection.py:671`
Python3 code: chunk_len = int(chunk_len_str.strip(), 16)

Notably, though the equation `int("0_0")` equates to `int("+0")`, `int("-0")`, and `int("0")`, using the 'int' constructor as a strategy for validating and parsing strings containing ASCII digits only is proven inadequate.

Tornado web framework affected versions contain a performance vulnerability in their HTTP cookie parser. When processing specially crafted malicious cookie headers, the parser's algorithm can exhibit quadratic time complexity. Since this parsing happens in the main event loop thread, it can cause the server to become unresponsive and block the processing of other incoming requests due to excessive CPU usage.

When Tornado's multipart/form-data parser encounters certain errors, it logs a warning but continues trying to parse the remainder of the data. This allows remote attackers to generate an extremely high volume of logs, constituting a DoS attack. This DoS is compounded by the fact that the logging subsystem is synchronous.

Tornado 6.3.2 includes a fix for CVE-2023-28370: Open redirect vulnerability in Tornado versions 6.3.1 and earlier allows a remote unauthenticated attacker to redirect a user to an arbitrary web site and conduct a phishing attack by having user access a specially crafted URL.

Tornado’s curl_httpclient.CurlAsyncHTTPClient class is vulnerable to CRLF (carriage return/line feed) injection in the request headers.

Hiredis (python wrapper for hiredis) 2.1.0 supports hiredis 1.1.0, that includes a security fix.
https://github.com/redis/hiredis-py/pull/135

An issue in Gevent before version 23.9.0 allows a remote attacker to escalate privileges via a crafted script to the WSGIServer component.

Affected versions of gevent are potentially vulnerable to a Race Condition leading to Unauthorized Access — CWE-362.

Affected versions of gevent were potentially vulnerable to HTTP request smuggling. The issue existed in the pywsgi Input._send_100_continue handling.

Affected versions of the Werkzeug package are vulnerable to Denial of Service (DoS) due to improper handling of Windows special device names in the safe_join function. In Werkzeug versions before 3.1.4, safe_join permits path segments such as “CON” or “AUX” to pass validation, allowing send_from_directory to construct a path that resolves to a Windows device file, which opens successfully but then blocks indefinitely when read.

Werkzeug 2.2.3 includes a fix for CVE-2023-25577: Prior to version 2.2.3, Werkzeug's multipart form data parser will parse an unlimited number of parts, including file parts. Parts can be a small amount of bytes, but each requires CPU time to parse and may use more memory as Python data. If a request can be made to an endpoint that accesses 'request.data', 'request.form', 'request.files', or 'request.get_data(parse_form_data=False)', it can cause unexpectedly high resource usage. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests. The amount of RAM required can trigger an out of memory kill of the process. Unlimited file parts can use up memory and file handles. If many concurrent requests are sent continuously, this can exhaust or kill all available workers.
https://github.com/pallets/werkzeug/security/advisories/GHSA-xg9f-g7g7-2323

Affected versions of Werkzeug are potentially vulnerable to resource exhaustion when parsing file data in forms. Applications using 'werkzeug.formparser.MultiPartParser' to parse 'multipart/form-data' requests (e.g. all flask applications) are vulnerable to a relatively simple but effective resource exhaustion (denial of service) attack. A specifically crafted form submission request can cause the parser to allocate and block 3 to 8 times the upload size in main memory. There is no upper limit; a single upload at 1 Gbit/s can exhaust 32 GB of RAM in less than 60 seconds.

Werkzeug 3.0.1 and 2.3.8 include a security fix: Slow multipart parsing for large parts potentially enabling DoS attacks.
https://github.com/pallets/werkzeug/commit/b1916c0c083e0be1c9d887ee2f3d696922bfc5c1

Werkzeug is a comprehensive WSGI web application library. If an upload of a file that starts with CR or LF and then is followed by megabytes of data without these characters: all of these bytes are appended chunk by chunk into internal bytearray and lookup for boundary is performed on growing buffer. This allows an attacker to cause a denial of service by sending crafted multipart data to an endpoint that will parse it. The amount of CPU time required can block worker processes from handling legitimate requests.

Werkzeug 2.2.3 includes a fix for CVE-2023-23934: Browsers may allow "nameless" cookies that look like '=value' instead of 'key=value'. A vulnerable browser may allow a compromised application on an adjacent subdomain to exploit this to set a cookie like '=__Host-test=bad' for another subdomain. Werkzeug prior to 2.2.3 will parse the cookie '=__Host-test=bad' as __Host-test=bad'. If a Werkzeug application is running next to a vulnerable or malicious subdomain which sets such a cookie using a vulnerable browser, the Werkzeug application will see the bad cookie value but the valid cookie key.
https://github.com/pallets/werkzeug/security/advisories/GHSA-px8h-6qxv-m22q

Affected versions of Werkzeug are vulnerable to Path Traversal (CWE-22) on Windows systems running Python versions below 3.11. The safe_join() function failed to properly detect certain absolute paths on Windows, allowing attackers to potentially access files outside the intended directory. An attacker could craft special paths starting with "/" that bypass the directory restrictions on Windows systems. The vulnerability exists in the safe_join() function which relied solely on os.path.isabs() for path validation. This is exploitable on Windows systems by passing paths starting with "/" to safe_join(). To remediate, upgrade to the latest version which includes additional path validation checks. 
NOTE: This vulnerability specifically affects Windows systems running Python versions below 3.11 where ntpath.isabs() behavior differs.

Werkzeug is a comprehensive WSGI web application library. The debugger in affected versions of Werkzeug can allow an attacker to execute code on a developer's machine under some circumstances. This requires the attacker to get the developer to interact with a domain and subdomain they control, and enter the debugger PIN, but if they are successful it allows access to the debugger even if it is only running on localhost. This also requires the attacker to guess a URL in the developer's application that will trigger the debugger.

Sqlalchemy 2.0.0b1 avoids leaking cleartext passwords to the open for careless uses of str(engine.URL()) in logs and prints.
https://github.com/sqlalchemy/sqlalchemy/pull/8563

Sqlalchemy-utils from version 0.27.0 'EncryptedType' uses by default AES with CBC mode. The IV that it uses is not random though.
https://github.com/kvesteri/sqlalchemy-utils/issues/166
https://github.com/kvesteri/sqlalchemy-utils/pull/499