filelock: StrictSoftFileLock follows a symbolic link swapped in at <path>.filelock and creates claim files in a directory another local user chooses

影響: pip:filelock >= 3.30.0, <= 4.2.0 → 4.2.1

StrictSoftFileLock and AsyncStrictSoftFileLock check .filelock (the coordination directory that holds the lock's state) with one lstat call on its name. lstat reports what a name is without following a symbolic link (a file that redirects to another path). After that check, the code reaches .filelock/claims by pathname for every later operation (mkdir, scan, publish, link, unlink). _open_directory passes O_NOFOLLOW (a flag that makes an open fail when the final name is a symbolic link), but the…

Read on GitHub Advisory Database

On 10/29/2026, 06:08 AM, GitHub Advisory Database published "filelock: StrictSoftFileLock follows a symbolic link swapped in at <path>.filelock and creates claim files in a directory another local user chooses" (type: Advisory). Severity is "Medium" (medium). Related technologies: Python. CVE: CVE-2026-112938.