CVE-2026-12345

Impact

The cleanup of tempfile.TemporaryDirectory is vulnerable to a race condition. An attacker who can modify the tree during cleanup can replace a directory with a symbolic link, causing files outside of the temporary directory to be deleted or have their permissions and file flags reset, with the privileges of the process performing the cleanup. Note that platforms where shutil.rmtree.avoids_symlink_attacks is false, remain affected, and file flags may still be reset outside of the tree on all platforms.

Affected packages

This record carries no package version data, so it cannot be matched against a dependency list automatically. Read the advisory and compare your version by hand.

Weakness classification

References

• NVD record
• CVE.org record
• https://github.com/python/cpython/commit/0478b52788117db4b831b3efd648f56b777628aa
• https://github.com/python/cpython/commit/06ef3d43fdaf4da97af12fa694b4886092c4b970
• https://github.com/python/cpython/commit/458e7134a5af7f86aee9d21b51cf499b41aa4420
• https://github.com/python/cpython/commit/58ed0259cae509a19138795df302fe60b544dc74
• https://github.com/python/cpython/commit/5c20517a4fc56683efe63a7751020db9573f538d
• https://github.com/python/cpython/commit/c39b52d00b42200aaadff679e2fe3f1006d57c58
• https://github.com/python/cpython/commit/e1f3590f155c6d66007e958c98c9d69316551993
• https://github.com/python/cpython/issues/157579
• https://github.com/python/cpython/pull/157580
• http://www.openwall.com/lists/oss-security/2026/09/29/40