filelock: SoftReadWriteLock follows a lock tree swapped in after its first acquire and writes lock records into directories of the user running the lock

影響: pip:filelock >= 4.1.0, <= 4.2.0 → 4.2.1

SoftReadWriteLock (and AsyncSoftReadWriteLock, which wraps one) checks once per lock object, by name, that .rw, .rw/gen and .rw/holders are real directories and not symbolic links (files that redirect to another path). It then keeps only a boolean. Every later record operation resolves the full path again, and O_NOFOLLOW (a flag that makes an open fail when the final name is a symbolic link) protects the last component only. Another local user (the other user below) who can write the directory…

GitHub Advisory Databaseで読む

2026/10/29 06:09、GitHub Advisory Databaseが「filelock: SoftReadWriteLock follows a lock tree swapped in after its first acquire and writes lock records into directories of the user running the lock」を公開しました (種別: 脆弱性アドバイザリ)。重大度は「注意」(low) です。関連する技術: Python。CVE: CVE-2026-112941。