CVE-2026-112940: tox-dev filelock

CVSS 7.1 (high) · published 2026-10-20

filelock is a platform-independent file lock for Python. From 3.20.4 until 4.2.1, ReadWriteLock let SQLite reopen the database and side files by name; on POSIX systems an attacker with rename access in a non-sticky parent can swap those names to cause overwrite or unlink operations, while a writable adjacent hot journal is additionally required for attacker-chosen content overwrites. This issue is fixed in version 4.2.1.

Affected products (NVD): tox-dev filelock

Fixed in (NVD): 4.2.1

Weakness: CWE-363, CWE-59

Source: NVD CVE-2026-112940

References

• https://github.com/tox-dev/filelock/commit/5e3f2ec0c5fb17cb2635b60b2b68bc63ab81ca2d
• https://github.com/tox-dev/filelock/pull/834
• https://github.com/tox-dev/filelock/releases/tag/4.2.1
• https://github.com/tox-dev/filelock/security/advisories/GHSA-v4x8-3wr5-3wq8
• https://github.com/tox-dev/filelock/security/advisories/GHSA-v4x8-3wr5-3wq8

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