CVE-2026-112937

filelock: ReadWriteLock on the hard-link route deletes any directory another user renames onto its .filelock-* link directory name

Published Oct 20, 2026 CVSS 3.1 · 6.1 Medium EPSS < 1% KEV · Not listed
Description
filelock is a platform-independent file lock for Python. From 4.1.0 until 4.2.1, ReadWriteLock can remove a randomized .filelock-* private-hard-link directory during cleanup, allowing another local user with rename access in a non-sticky parent to observe a live name or forge a dead-owner sweep name and rename a sibling directory onto it for deletion. This issue is fixed in version 4.2.1.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-jqc4-5cvw-7w85 filelock: ReadWriteLock on the hard-link route deletes any directory another user renames onto its .filelock-* link directory name
History
Type Values Removed Values Added
CPEs cpe:2.3:a:tox-dev:filelock:*:*:*:*:*:python:*:*
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Tox-dev
Tox-dev filelock
Vendors & Products Tox-dev
Tox-dev filelock
Type Values Removed Values Added
Description filelock is a platform-independent file lock for Python. From 4.1.0 until 4.2.1, ReadWriteLock can remove a randomized .filelock-* private-hard-link directory during cleanup, allowing another local user with rename access in a non-sticky parent to observe a live name or forge a dead-owner sweep name and rename a sibling directory onto it for deletion. This issue is fixed in version 4.2.1.
Title filelock: ReadWriteLock on the hard-link route deletes any directory another user renames onto its .filelock-* link directory name
Weaknesses CWE-367
References
Metrics cvssV3_1

{'score': 6.1, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Oct 21, 2026, 3:55 PM
Reserved
Oct 19, 2026, 9:30 PM
Status
Analyzed
Published
Oct 20, 2026, 3:17 PM
Modified
Oct 21, 2026, 6:05 PM