Description
filelock is a platform-independent file lock for Python. From 4.1.0 until 4.2.1, SoftReadWriteLock and AsyncSoftReadWriteLock cache a successful check of the <path>.rw lock tree and resolve its names again during later record operations, allowing another local user who can replace that tree after the first acquisition to redirect lock-record writes into directories writable by the lock user. This issue is fixed in version 4.2.1.
Affected products
tox-dev: filelock
References5
- github.com/tox-dev/filelock/security/advisories/GHSA-wfhq-q4j2-… ExploitMitigationPatchVendor Advisory
- github.com/tox-dev/filelock/security/advisories/GHSA-wfhq-q4j2-… ExploitMitigationPatchVendor 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
-
3.3
LOW
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N - EPSS — exploit probability
- 0% percentile: 3 · as of 9 November 2026
- CWE
- CWE-367
Could this be exploited in your environment?
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