CVE-2026-112939
filelock: SoftFileLock removes a live holder's marker when another user forges the PID in a writable marker
- State
- Published
- Severity
- 4.7 Medium
- Published
- Oct 20, 2026
- Updated
- Oct 20, 2026
- Reserved
- Oct 19, 2026
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 3.1 | 4.7 Medium | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:N | GitHub_M |
Weaknesses
- CWE-345 Insufficient Verification of Data Authenticity
Affected Products
| Product | Versions |
|---|---|
filelocktox-dev |
|
References
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