CVE-2026-112936Medium· 6.1▾ TwilightPoC availablefilelock is a platform-independent file lock for Python. From 3.20.4 until 4.0.9, ReadWriteLock and AsyncReadWriteLock versions from 3.20.4 resolve the lock path and pass it to SQLite without rejecting a final symbolic link, allowing ano…
▾ Twilight zone — High severity, or a signal on a lesser flaw
impact 33.6 · likelihood 0 · exploitation 12
A public proof-of-concept already exists for this vulnerability — see Exploit availability below.
Stakeholder-Specific Vulnerability Categorization from CISA's ADP record at CVE.org: whether exploitation is observed, whether an attack can be automated, and how much of the system is at stake. The CVSS score shown above comes from the assigning CNA record, not NVD.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via CVEORG
Exploit / PoC code exists
filelock is a platform-independent file lock for Python. From 3.20.4 until 4.0.9, ReadWriteLock and AsyncReadWriteLock versions from 3.20.4 resolve the lock path and pass it to SQLite without rejecting a final symbolic link, allowing another local user who can create names in the lock directory to redirect database creation and locking or split mutual exclusion between targets. This issue is fixed in version 4.0.9.
filelock >= 3.20.4, < 4.0.9Refer to the linked advisories for vendor-supplied fixes and affected version ranges.
Field changes observed since this record was first indexed.
Connected by shared product, vendor, weakness, or advisory.
CVE-2026-112912Low· 2.5filelock: Symlink swap during SoftFileLock's writability check leaks whether a path exists and is writable by the lock taker
CVE-2026-112906Medium· 4.7filelock: SoftFileLock evicts a fresh lock file whose watched age another local user's pre-dated file passed on through inode reuse
CVE-2026-112915Medium· 5.5filelock ReadWriteLock: a crafted lock database makes every acquire stall or hang regardless of timeout
CVE-2026-112939Medium· 4.7filelock: SoftFileLock removes a live holder's marker when another user forges the PID in a writable marker
CVE-2026-112909Medium· 6.1filelock: UnixFileLock truncates and chmods any regular file another user renames or hard-links onto the lock path
CVE-2026-112911Medium· 6.3filelock: StrictSoftFileLock and SoftReadWriteLock adopt a protocol directory another user created first, losing mutual exclusion