CVE-2026-11940

tarfile.extractall() with the 'data' or 'tar' filter could be bypassed by a crafted archive where a hardlink references a symlink stored at a deeper name than the hardlink itself.  The extraction fallback validated the symlink at it's archived location but recreated it at the hardlink's shallower path, letting a relative target the filter judged contained escape the destination directory.  This allowed a malicious tar archive to create a symlink pointing outside the destination, enabling out-of-destination file reads or writes. This was an incomplete fix of CVE-2025-4330.

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• python3.14
• python3.13
• python3.11
• python3.9
• python2.7
• pypy3 https://github.com/python/cpython/issues/151558 https://github.com/python/cpython/pull/151559 https://github.com/python/cpython/commit/672825e2f36a57e173959b0d9d409d4560dab8df (3.15 branch) https://github.com/python/cpython/commit/79c06bd5c6afa3c440d50faf7ee1b147c8832b4c (3.14 branch) https://github.com/python/cpython/commit/771d12dda5140313db0ac550292987975651bbde (3.13 branch)