Bypass extraction filter to modify file metadata outside extraction directory

Vulnerability Description

Allows modifying some file metadata (e.g. last modified) with filter="data" or file permissions (chmod) with filter="tar" of files outside the extraction directory. You are affected by this vulnerability if using the tarfile module to extract untrusted tar archives using TarFile.extractall() or TarFile.extract() using the filter= parameter with a value of "data" or "tar". See the tarfile extraction filters documentation https://docs.python.org/3/library/tarfile.html#tarfile-extraction-filter  for more information. Only Python versions 3.12 or later are affected by these vulnerabilities, earlier versions don't include the extraction filter feature. Note that for Python 3.14 or later the default value of filter= changed from "no filtering" to `"data", so if you are relying on this new default behavior then your usage is also affected. Note that none of these vulnerabilities significantly affect the installation of source distributions which are tar archives as source distributions already allow arbitrary code execution during the build process. However when evaluating source distributions it's important to avoid installing source distributions with suspicious links.

References

• https://github.com/python/cpython/issues/135034
• https://github.com/python/cpython/pull/135037
• https://github.com/python/cpython/issues/127987
• https://mail.python.org/archives/list/security-announce@python.org/thread/MAXIJJCUUMCL7ATZNDVEGGHUMQMUUKLG/
• https://github.com/python/cpython/commit/3612d8f51741b11f36f8fb0494d79086bac9390a
• https://github.com/python/cpython/commit/9e0ac76d96cf80b49055f6d6b9a6763fb9215c2a
• https://gist.github.com/sethmlarson/52398e33eff261329a0180ac1d54f42f
• https://github.com/python/cpython/commit/19de092debb3d7e832e5672cc2f7b788d35951da
• https://github.com/python/cpython/commit/28463dba112af719df1e8b0391c46787ad756dd9
• https://github.com/python/cpython/commit/4633f3f497b1ff70e4a35b6fe2c907cbe2d4cb2e
• https://github.com/python/cpython/commit/9c1110ef6652687d7c55f590f909720eddde965a
• https://github.com/python/cpython/commit/aa9eb5f757ceff461e6e996f12c89e5d9b583b01
• https://github.com/python/cpython/commit/dd8f187d0746da151e0025c51680979ac5b4cfb1