Description
filelock is a platform-independent file lock for Python. Prior to 4.2.1, UnixFileLock can truncate a regular file renamed onto the lock path when another local user has actual rename permission, or hard-linked there under a permissive hard-link policy; when an explicit mode is requested, affected versions from 3.10.2 can also change that file's mode. This issue is fixed in version 4.2.1.
Affected products
tox-dev: filelock
References5
- github.com/tox-dev/filelock/security/advisories/GHSA-69hj-f68j-… ExploitMitigationPatchVendor Advisory
- github.com/tox-dev/filelock/security/advisories/GHSA-69hj-f68j-… ExploitMitigationPatchVendor Advisory
- github.com/tox-dev/filelock/commit/e1e825b1992f69fb6b346dc395d5… Patch
- github.com/tox-dev/filelock/pull/835 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:L/I:H/A:N - EPSS — exploit probability
- 0% percentile: 13 · as of 9 November 2026
- CWE
- CWE-706
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