Description
filelock is a platform-independent file lock for Python. From 3.20.4 until 4.2.1, ReadWriteLock can open a crafted SQLite lock database without bounding schema and query work, allowing another local user who can replace the database to make acquisition stall or hang; versions from 3.20.4 expose this on initial per-instance opening, and versions from 3.30.0 repeat the exposure on every acquisition. This issue is fixed in version 4.2.1.
Affected products
tox-dev: filelock
References5
- github.com/tox-dev/filelock/security/advisories/GHSA-cwqr-hh33-… ExploitMitigationPatchVendor Advisory
- github.com/tox-dev/filelock/security/advisories/GHSA-cwqr-hh33-… 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
-
5.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 12 · as of 9 November 2026
- CWE
- CWE-400
Could this be exploited in your environment?
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