Description
filelock is a platform-independent file lock for Python. From 3.30.0 until 4.2.1, StrictSoftFileLock versions from 3.30.0 and SoftReadWriteLock versions from 4.0.0 can adopt a protocol directory created first by another local user in a shared parent directory, allowing that user to alter protocol state and admit concurrent holders. This issue is fixed in version 4.2.1.
Affected products
tox-dev: filelock
References5
- github.com/tox-dev/filelock/security/advisories/GHSA-9c4x-gm8v-… ExploitMitigationPatchVendor Advisory
- github.com/tox-dev/filelock/security/advisories/GHSA-9c4x-gm8v-… ExploitMitigationPatchVendor Advisory
- github.com/tox-dev/filelock/commit/bfa066d65a1ba9106f86ee9d027f… Patch
- github.com/tox-dev/filelock/pull/839 Patch
- github.com/tox-dev/filelock/releases/tag/4.2.1 Release Notes
Metrics
- CVSS 3.1
-
6.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:H - EPSS — exploit probability
- 0% percentile: 4 · as of 9 November 2026
- CWE
- CWE-283
Could this be exploited in your environment?
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