CVE-2026-4360

In the Tarfile.extract() function, the filter parameter is not passed properly when extracting hardlinks. An affected system that extracts content from untrusted tar files could end up writing files with an unexpected uid/gid despite the user passing filter='data' to the extract() function.

• python3.14
• python3.13 [trixie] - python3.13 (Minor issue)
• python3.11 (Vulnerable code didn't get backported to the version in Bookworm)
• python3.9 (extraction filters (PEP 706) absent in 3.9.2; extract() has no filter parameter)
• python2.7 (extraction filters (PEP 706) absent in py2; extract() has no filter parameter)
• jython (extraction filters/PEP 706 absent in bundled python2.7 stdlib; tarfile.extract() has no filter parameter)
• pypy3 (bug https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1141531) [trixie] - pypy3 (Minor issue) [bookworm] - pypy3 (Vulnerable code backported down to stdlib-3.9.17; embedding 3.6.16) [bullseye] - pypy3 (Vulnerable code backported down to stdlib-3.9.17; embedding 3.6.9) https://mail.python.org/archives/list/security-announce@python.org/thread/TWZW2PC2AZOV6FENIHFSRC63OM7MBGSB/ https://github.com/python/cpython/issues/151987 https://github.com/python/cpython/pull/151988 https://github.com/python/cpython/commit/7b57e8d51446297b8c7c482d224bc5f1938e4301 (3.15 branch) https://github.com/python/cpython/commit/5e0ef3f1afe892e4f64eb83368db57ac4c40cba0 (3.14 branch) https://github.com/python/cpython/commit/eee3ddf0ca10283cc7fea724aae9cd8665f8d15e (3.13 branch) Same code situation as with CVE-2025-4435.