CVE-2026-112912: low-severity vulnerability in tox-dev filelock
filelock: Symlink swap during SoftFileLock's writability check leaks whether a path exists and is writable by the lock taker
Published
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
8Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 2.5epss 0.2%
filelock is a platform-independent file lock for Python. From 3.32.6 until 4.2.1, SoftFileLock can follow a swapped symbolic link during the conditional os.access writability check for a node without its owner-write bit, allowing another local user on a platform and directory configuration that follows the link to infer whether a chosen path exists and is writable from the observable acquisition result. This issue is fixed in version 4.2.1.
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N
Affected products
tox-dev · filelockRelated CVEs — tox-dev filelock
In the same product, most dangerous first.
CVE-2026-112934MEDIUMfilelock: SoftReadWriteLock holder refresh writes through a hard link and hangs on a named pipe that another local user renames over its recordEPSS 0.2%CVE-2026-112936MEDIUMfilelock: ReadWriteLock follows a symlink at the lock path into SQLiteEPSS 0.2%CVE-2026-112909MEDIUMfilelock: UnixFileLock truncates and chmods any regular file another user renames or hard-links onto the lock pathEPSS 0.2%CVE-2026-112915MEDIUMfilelock ReadWriteLock: a crafted lock database makes every acquire stall or hang regardless of timeoutEPSS 0.2%CVE-2025-68146MEDIUMfilelock has TOCTOU race condition that allows symlink attacks during lock file creationEPSS 0.2%CVE-2026-112940HIGHfilelock ReadWriteLock: SQLite reopens the lock database by name, so a planted symlink or journal file makes the lock user's process overwrite or unlink its own filesEPSS 0.2%