CVE-2026-112912Low· 2.5▾ TwilightPoC availablefilelock 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…
▾ Twilight zone — High severity, or a signal on a lesser flaw
impact 13.8 · 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 3.32.6 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.
filelock >= 3.32.6, < 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-2026-112909Medium· 6.1filelock: UnixFileLock truncates and chmods any regular file another user renames or hard-links onto the lock path
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-2026-112936Medium· 6.1filelock: ReadWriteLock follows a symlink at the lock path into SQLite
CVE-2026-112939Medium· 4.7filelock: SoftFileLock removes a live holder's marker when another user forges the PID in a writable marker
CVE-2026-112911Medium· 6.3filelock: StrictSoftFileLock and SoftReadWriteLock adopt a protocol directory another user created first, losing mutual exclusion