Description
filelock is a platform-independent file lock for Python. From 4.0.0 until 4.2.1, SoftReadWriteLock refreshes holder records by name, allowing another local user with rename access to the lock directory to replace a record with a named pipe and stall the lock, or under a permissive hard-link policy to link a reachable target file and cause the lock user to write through it. This issue is fixed in version 4.2.1.
Affected products
tox-dev: filelock
References5
- github.com/tox-dev/filelock/security/advisories/GHSA-fj95-fr6c-… ExploitMitigationVendor Advisory
- github.com/tox-dev/filelock/security/advisories/GHSA-fj95-fr6c-… ExploitMitigationVendor Advisory
- github.com/tox-dev/filelock/commit/bfa066d65a1ba9106f86ee9d027f… Patch
- github.com/tox-dev/filelock/pull/842 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:L/A:H - EPSS — exploit probability
- 0% percentile: 14 · as of 9 November 2026
- CWE
- CWE-62
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