Cpython

http.cookies.Morsel.js_output() returns an inline <script> snippet and only escapes " for JavaScript string context. It does not neutralize the HTML parser-sensitive sequence </script> inside the generated script element. Mitigation base64-encodes the cookie value to disallow escaping using cookie value.

Published: 2026-04-22T19:28:08.720Z
Updated: 2026-04-29T15:31:09.049Z

A vulnerability has been found in the CPython `venv` module and CLI where path names provided when creating a virtual environment were not quoted properly, allowing the creator to inject commands into virtual environment "activation" scripts (ie "source venv/bin/activate"). This means that attacker-controlled virtual environments are able to run commands when the virtual environment is activated. Virtual environments which are not created by an attacker or which aren't activated before being used (ie "./venv/bin/python") are not affected.

Published: 2024-10-22T16:34:39.210Z
Updated: 2025-11-03T22:33:21.116Z

There is a LOW severity vulnerability affecting CPython, specifically the 'http.cookies' standard library module. When parsing cookies that contained backslashes for quoted characters in the cookie value, the parser would use an algorithm with quadratic complexity, resulting in excess CPU resources being used while parsing the value.

Published: 2024-08-19T19:06:45.311Z
Updated: 2025-11-03T22:32:52.863Z

There is a MEDIUM severity vulnerability affecting CPython. The email module didn’t properly quote newlines for email headers when serializing an email message allowing for header injection when an email is serialized.

Published: 2024-08-01T13:40:11.069Z
Updated: 2025-11-03T22:32:47.018Z

There is a MEDIUM severity vulnerability affecting CPython. Regular expressions that allowed excessive backtracking during tarfile.TarFile header parsing are vulnerable to ReDoS via specifically-crafted tar archives.

Published: 2024-09-03T12:29:00.102Z
Updated: 2025-11-03T22:32:42.630Z

The “ipaddress” module contained incorrect information about whether certain IPv4 and IPv6 addresses were designated as “globally reachable” or “private”. This affected the is_private and is_global properties of the ipaddress.IPv4Address, ipaddress.IPv4Network, ipaddress.IPv6Address, and ipaddress.IPv6Network classes, where values wouldn’t be returned in accordance with the latest information from the IANA Special-Purpose Address Registries. CPython 3.12.4 and 3.13.0a6 contain updated information from these registries and thus have the intended behavior.

Published: 2024-06-17T15:05:58.827Z
Updated: 2025-11-03T21:57:16.975Z

On Windows a directory returned by tempfile.mkdtemp() would not always have permissions set to restrict reading and writing to the temporary directory by other users, instead usually inheriting the correct permissions from the default location. Alternate configurations or users without a profile directory may not have the intended permissions. If you’re not using Windows or haven’t changed the temporary directory location then you aren’t affected by this vulnerability. On other platforms the returned directory is consistently readable and writable only by the current user. This issue was caused by Python not supporting Unix permissions on Windows. The fix adds support for Unix “700” for the mkdir function on Windows which is used by mkdtemp() to ensure the newly created directory has the proper permissions.

Published: 2024-05-07T21:02:55.284Z
Updated: 2024-09-07T02:44:36.613Z

An issue was found in the CPython `zipfile` module affecting versions 3.12.1, 3.11.7, 3.10.13, 3.9.18, and 3.8.18 and prior. The zipfile module is vulnerable to “quoted-overlap” zip-bombs which exploit the zip format to create a zip-bomb with a high compression ratio. The fixed versions of CPython makes the zipfile module reject zip archives which overlap entries in the archive.

Published: 2024-03-19T15:12:07.789Z
Updated: 2025-11-03T21:50:58.107Z

An issue was found in CPython 3.12.0 `subprocess` module on POSIX platforms. The issue was fixed in CPython 3.12.1 and does not affect other stable releases. When using the `extra_groups=` parameter with an empty list as a value (ie `extra_groups=[]`) the logic regressed to not call `setgroups(0, NULL)` before calling `exec()`, thus not dropping the original processes' groups before starting the new process. There is no issue when the parameter isn't used or when any value is used besides an empty list. This issue only impacts CPython processes run with sufficient privilege to make the `setgroups` system call (typically `root`).

Published: 2023-12-08T18:20:49.583Z
Updated: 2024-08-02T08:35:13.267Z