CVE-2026-12345
Race condition in tempfile.TemporaryDirectory cleanup allows deleting files outside the temporary directory
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Description
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
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
Remediation
No guide yetNo remediation guidance has been written for this CVE yet. What the record does show:
Patch and advisory references
- https://github.com/python/cpython/pull/157580
- https://github.com/python/cpython/commit/5c20517a4fc56683efe63a7751020db9573f538d
- https://github.com/python/cpython/commit/458e7134a5af7f86aee9d21b51cf499b41aa4420
- https://github.com/python/cpython/commit/e1f3590f155c6d66007e958c98c9d69316551993
- https://github.com/python/cpython/commit/06ef3d43fdaf4da97af12fa694b4886092c4b970
References (10)
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