Vulnerability Description
filelock is a platform-independent file lock for Python. From 3.22.0 until 4.2.1, SoftFileLock can trust a forged process identifier in a marker that an attacker can modify but cannot remove, allowing an authorized contender such as another process of the holder's account or root to act as a confused deputy, remove the live marker, and admit another holder. This issue is fixed in version 4.2.1.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Tox-Dev | Filelock | >= 3.22.0, < 4.2.1 |
Related Weaknesses (CWE)
References
- https://github.com/tox-dev/filelock/commit/eeceaa846cbe4df72718d94c8371ca1ab8f5bPatch
- https://github.com/tox-dev/filelock/pull/836Patch
- https://github.com/tox-dev/filelock/releases/tag/4.2.1Release Notes
- https://github.com/tox-dev/filelock/security/advisories/GHSA-rfpc-qcw5-3pc4ExploitMitigationPatch
- https://github.com/tox-dev/filelock/security/advisories/GHSA-rfpc-qcw5-3pc4ExploitMitigationPatch
FAQ
What is CVE-2026-112939?
CVE-2026-112939 is a vulnerability with a CVSS score of 4.7 (MEDIUM). filelock is a platform-independent file lock for Python. From 3.22.0 until 4.2.1, SoftFileLock can trust a forged process identifier in a marker that an attacker can modify but cannot remove, allowing...
How severe is CVE-2026-112939?
CVE-2026-112939 has been rated MEDIUM with a CVSS base score of 4.7/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-112939?
Check the references section above for vendor advisories and patch information. Affected products include: Tox-Dev Filelock.