Vulnerability in Tox-Dev Filelock
CVE-2026-112910
filelock is a platform-independent file lock for Python. From 3.10.0 until 4.2.1, filelock on Windows ignores the mode argument for WindowsFileLock files and the ReadWriteLock SQLite database. A lock created with mode=0o600 receives the parent directory's inheritable ACL because _open_non_reparse_fd and _nt_open do not create an owner-only security descriptor. Another local account with inherited access can read holder metadata or the lock database, modify those files where the ACL permits writes, or take the byte-range lock after release and delay later acquisitions. UnixFileLock is not affected, and mutual exclusion between cooperating processes continues to hold. This issue is fixed in version 4.2.1.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
- Tox-Dev Filelock — versions >= 3.10.0, < 4.2.1
Weakness classification (CWE)
References
- https://github.com/tox-dev/filelock/commit/72786d41aa25159ad28c1bcf4291738b135b2c6c
- https://github.com/tox-dev/filelock/commit/e1e825b1992f69fb6b346dc395d5ae4893536c0a
- https://github.com/tox-dev/filelock/pull/835
- https://github.com/tox-dev/filelock/releases/tag/4.2.1
- https://github.com/tox-dev/filelock/security/advisories/GHSA-8mx5-7m5m-r77g
Frequently asked questions
- What is CVE-2026-112910?
- CVE-2026-112910 is a medium-severity vulnerability in Tox-Dev Filelock, classified under Incorrect Permission Assignment for Critical Resource. CVSS score: 5.3/10. Published 2026-11-05.
- How severe is CVE-2026-112910?
- Medium severity. CVSS v3 base score is 5.3 out of 10.