CVE-2026-112934Medium· 6.1▾ TwilightPoC availablefilelock is a platform-independent file lock for Python. From 4.0.0 until 4.2.1, SoftReadWriteLock refreshes holder records by name, allowing another local user with rename access to the lock directory to replace a record with a named pi…
▾ 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.
Exploit-prediction probability, daily snapshots since Oct 22.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via CVEORG
Last analysed / modified upstream
0.1%
Exploit / PoC code exists
0.1% → 0.2%
filelock is a platform-independent file lock for Python. From 4.0.0 until 4.2.1, SoftReadWriteLock refreshes holder records by name, allowing another local user with rename access to the lock directory to replace a record with a named pipe and stall the lock, or under a permissive hard-link policy to link a reachable target file and cause the lock user to write through it. This issue is fixed in version 4.2.1.
filelock >= 4.0.0, < 4.2.1Refer 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-2026-112941Low· 3.3filelock: SoftReadWriteLock follows a lock tree swapped in after its first acquire and writes lock records into directories of the user running the lock
CVE-2026-112911Medium· 6.3filelock: StrictSoftFileLock and SoftReadWriteLock adopt a protocol directory another user created first, losing mutual exclusion
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-2026-112909Medium· 6.1filelock: UnixFileLock truncates and chmods any regular file another user renames or hard-links onto the lock path
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-2026-112939Medium· 4.7filelock: SoftFileLock removes a live holder's marker when another user forges the PID in a writable marker