← Back to CVE List
CVE-2026-11940NVD
Vulnerability Summary
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.
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.
CVSS v4.0 Base Metrics — Score 7.8 (HIGH)
Attack VectorNetwork
Attack ComplexityLow
Attack RequirementsNone
Privileges RequiredNone
User InteractionNone
Confidentiality (Vulnerable System)None
Integrity (Vulnerable System)None
Availability (Vulnerable System)None
Confidentiality (Subsequent System)High
Integrity (Subsequent System)High
Availability (Subsequent System)None
Affected & Patched Versions
- Python Software Foundation CPython < 3.10.21
- Python Software Foundation CPython >= 3.11.0 and < 3.11.16
- Python Software Foundation CPython >= 3.12.0 and < 3.12.14
- Python Software Foundation CPython >= 3.13.0 and < 3.13.15
- Python Software Foundation CPython >= 3.14.0 and < 3.14.7
- Python Software Foundation CPython >= 3.15.0a1 and < 3.15.0b4
- Python Software Foundation CPython 3.10.21
- Python Software Foundation CPython 3.11.16
- Python Software Foundation CPython 3.12.14
- Python Software Foundation CPython 3.13.15
- Python Software Foundation CPython 3.14.7
- Python Software Foundation CPython 3.15.0b4
External References
- https://github.com/python/cpython/pull/151559
- https://mail.python.org/archives/list/security-announce@python.org/thread/LD6QIISNQFQYOIEPJNEUIPV7S3V76FZH/
- https://github.com/python/cpython/issues/151558
- https://github.com/python/cpython/commit/27dd970bf6b17ebca7c8ed486a40ab043ed7af8f
- https://github.com/python/cpython/commit/672825e2f36a57e173959b0d9d409d4560dab8df
- https://github.com/python/cpython/commit/771d12dda5140313db0ac550292987975651bbde
- https://github.com/python/cpython/commit/79c06bd5c6afa3c440d50faf7ee1b147c8832b4c
- https://github.com/python/cpython/commit/be13e86f6b9788a6f4d0419dffef72cbae5865c9
- https://github.com/python/cpython/commit/e5fdbd8d5aa923bd9111b112ea73bd6ec7c47877
- https://github.com/python/cpython/commit/0f852b3f07dd8e71e40326a51c02afbf16a42cc5