Click 8.0.0 uses 'mkstemp()' instead of the deprecated & insecure 'mktemp()'.
https://github.com/pallets/click/issues/1752

Affected versions of the Flask package are vulnerable to Information Disclosure due to missing cache-variation headers when the session object is accessed via certain code paths. In Flask’s session handling, accessing flask.session is intended to set a Vary: Cookie response header, but session key-only access patterns (such as using the Python in operator to test for a key without reading or mutating session values) can bypass the logic that adds the header.

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

Affected versions of this package are vulnerable to Insufficient Verification of Data Authenticity. The library does not validate the `crit` (Critical) Header Parameter as required by RFC 7515 §4.1.11 — when a JWT contains a `crit` array listing extensions that the library does not understand, the token is accepted instead of rejected. An attacker can exploit this vulnerability by crafting JWTs with unknown critical extensions (e.g., MFA requirements, token binding, scope restrictions) that are silently ignored, potentially bypassing security policies or causing split-brain verification in mixed-library deployments where other RFC-compliant libraries would reject the same token.

PyJWT 2.4.0 includes a fix for CVE-2022-29217: An attacker submitting the JWT token can choose the used signing algorithm. The PyJWT library requires that the application chooses what algorithms are supported. The application can specify 'jwt.algorithms.get_default_algorithms()' to get support for all algorithms, or specify a single algorithm. The issue is not that big as 'algorithms=jwt.algorithms.get_default_algorithms()' has to be used. As a workaround, always be explicit with the algorithms that are accepted and expected when decoding.

Sphinx 3.0.4 updates jQuery version from 3.4.1 to 3.5.1 for security reasons.

Sphinx 3.0.4 updates jQuery version from 3.4.1 to 3.5.1 for security reasons.

Sphinx 3.3.0 includes a fix for a ReDoS vulnerability in inventory.
https://github.com/sphinx-doc/sphinx/issues/8175
https://github.com/sphinx-doc/sphinx/commit/f7b872e673f9b359a61fd287a7338a28077840d2

Sphinx 3.3.0 includes a fix for a ReDoS vulnerability in docstring.
https://github.com/sphinx-doc/sphinx/issues/8172
https://github.com/sphinx-doc/sphinx/commit/f00e75278c5999f40b214d8934357fbf0e705417

Twine 2.0.0 updates requests to 2.20 (or later) to include a security fix.

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 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

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.

In Pallets Werkzeug before 0.15.5, SharedDataMiddleware mishandles drive names (such as C:) in Windows pathnames.

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-2023-23934: 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

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.

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 0.15.5 includes a fix for an information disclosure vulnerability.
https://github.com/pallets/werkzeug/pull/1592

Affected versions of the Werkzeug package are vulnerable to Denial of Service (DoS) due to improper handling of Windows special device names in path joining logic. The safe_join() function fails to reject device-name path segments when they are preceded by other segments (for example, example/NUL), and send_from_directory() relies on safe_join() when resolving user-supplied file paths.

Affected versions of the Werkzeug package are vulnerable to Improper Handling of Windows Device Names due to incomplete validation of Windows reserved device names in user-controlled path segments. In werkzeug.security.safe_join, path components ending with special device names (for example CON or AUX) are not reliably rejected when they include compound extensions (for example CON.txt.html) or trailing spaces, and werkzeug.utils.send_from_directory relies on safe_join when resolving a requested filename.

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

Cookiecutter 2.1.1 includes a fix for CVE-2022-24065: Cookiecutter before 2.1.1 is vulnerable to Command Injection via hg argument injection. When calling the cookiecutter function from Python code with the checkout parameter, it is passed to the hg checkout command in a way that additional flags can be set. The additional flags can be used to perform a command injection.