## filelock: SoftFileLock stale-break restore follows a swapped-in symbolic link and hard-links a file of the user running the lock into the lock directory

- 種別: advisory
- 重大度: medium
- 関連技術: python
- CVE: CVE-2026-112914
- 公開日時: 2026-10-23T22:00:11.000Z
- 情報源: GitHub Advisory Database (https://github.com/advisories/GHSA-crv4-6mhj-j5jh)
- パーマリンク: https://vulnpulse.app/items/ghsa-ghsa-crv4-6mhj-j5jh

影響: pip:filelock >= 4.1.0, <= 4.2.0 → 4.2.1
When a soft-lock stale break finds that the marker (the lock file at ) it renamed aside was a live one recreated by a successor, the restore branch of break_lock_file() checks the break name with lstat (a check that reads a name without following a symbolic link) and then calls os.link(break_path, lock_file) by name. On CPython 3.12 and later on Linux (and on macOS) that call follows a symbolic link (a file that redirects to another path). A local user (the other user below) who can write a sha…