CVE-2026-112939

Published: Oct 20, 2026Modified: Oct 21, 2026

4.7

Vector

CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:N

Exploitability: 1.0 / Impact: 3.6

Source: security-advisories@github.com (Secondary)

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.

Affected (1)

Products: Tox Dev: Filelock

1 product

Configuration A

1 vulnerable

Vulnerable Software	Affected Versions
Tox Dev Filelock	3.22.0 ≤ version < 4.2.1

Related CWEs

Insufficient Verification of Data Authenticity

The product does not sufficiently verify the origin or authenticity of data, in a way that causes it to accept invalid data.

References (5)

https://github.com/tox-dev/filelock/commit/eeceaa846cbe4df72718d94c8371ca1ab8f5b3cc

Source: security-advisories@github.com

Patch

https://github.com/tox-dev/filelock/pull/836

Source: security-advisories@github.com

Patch

https://github.com/tox-dev/filelock/releases/tag/4.2.1

Source: security-advisories@github.com

Release Notes

https://github.com/tox-dev/filelock/security/advisories/GHSA-rfpc-qcw5-3pc4

Source: security-advisories@github.com

ExploitMitigationPatchVendor Advisory

https://github.com/tox-dev/filelock/security/advisories/GHSA-rfpc-qcw5-3pc4

Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0

ExploitMitigationPatchVendor Advisory

Timeline

No history available yet.