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.
Affected products
tox-dev: filelock
References4
- github.com/tox-dev/filelock/security/advisories/GHSA-jqc4-5cvw-… ExploitMitigationPatchVendor Advisory
- github.com/tox-dev/filelock/commit/5e3f2ec0c5fb17cb2635b60b2b68… Patch
- github.com/tox-dev/filelock/pull/834 Patch
- github.com/tox-dev/filelock/releases/tag/4.2.1 Release Notes
Metrics
- CVSS 3.1
-
6.1
MEDIUM
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L - EPSS — exploit probability
- 0% percentile: 5 · as of 9 November 2026
- CWE
- CWE-367
Could this be exploited in your environment?
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