{"items":[{"id":"NVI-00009217","kind":"vulnerability","title":"filelock: ReadWriteLock follows a symlink at the lock path into SQLite","revision":1,"unknowns":["Customer inventory, deployment, reachability and exploitation have not been inspected."],"lifecycle":"active","identifiers":["GHSA-j8f7-rjxc-mr56","CVE-2026-112936"],"plain_summary":"GitHub lists this reviewed advisory for filelock. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.","review_status":"source_listed","control_topics":[],"public_actions":[{"summary":"Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.","source_ids":["sr-fbf4f37dfea4dfb84045d2dfb2302096"],"action_type":"investigate","limitations":"Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system.","current_supported_target":null}],"schema_version":"1.1.0","source_metrics":[{"kind":"CVSS","as_of":"2026-10-28T21:08:32.000Z","value":"6.1 medium","meaning":"GitHub source severity; exploitability and local consequence require separate evidence.","source_id":"sr-fbf4f37dfea4dfb84045d2dfb2302096"}],"why_it_matters":"Published affected context helps an owner decide what evidence to gather. This report has not examined your application.","related_sources":[{"id":"sr-fbf4f37dfea4dfb84045d2dfb2302096","url":"https://github.com/advisories/GHSA-j8f7-rjxc-mr56","basis":"vendor_advisory","notes":"GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.","title":"GHSA-j8f7-rjxc-mr56","publisher":"GitHub Advisory Database","observed_at":"2026-10-31T21:56:08.420Z"}],"affected_context":[{"certainty":"source_listed","source_ids":["sr-fbf4f37dfea4dfb84045d2dfb2302096"],"technology":"filelock","known_exclusions":[],"conditions_summary":"### Summary\n\n`ReadWriteLock` and `AsyncReadWriteLock` resolve the lock path with `pathlib.Path.resolve()` and pass it to `sqlite3.connect()` without refusing a symlink. A local user who can create names in the lock's directory, such as `/tmp` or a shared cache, can plant a symlink at the lock path and make the victim's process create, lock, or write the file it points to, or break mutual exclusion between the victim's own processes.\n\n### Details\n\n`ReadWriteLock.__init__` stores `pathlib.Path(lock_file).resolve()`, which follows a final symlink, and every connection opens that path through `sqlite3.connect()` with no `O_NOFOLLOW` or regular-file check. SQLite's own VFS also resolves the final symlink in user space, so `fs.protected_symlinks` and the sticky bit do not help: the kernel never sees a symlink to refuse. The other lock classes do not follow a final symlink: `FileLock` opens with `O_NOFOLLOW`, and `SoftReadWriteLock` coordinates through `.rw/`.\n\n### Proof of concept\n\nOn Linux, with the victim and attacker as different users and `/shared` mode 1777 with `fs.protected_symlinks=1`:\n\n1. The attacker runs `ln -s /home/victim/private/pwned.flag /shared/app.rwlock.db`.\n2. T","public_affected_ranges":[">= 3.20.4, <= 4.0.8"]}],"null_published_at":"2026-10-31T22:13:31.290Z","source_updated_at":"2026-10-28T21:08:32.000Z","source_disclosed_at":"2026-10-28T21:08:30.000Z","is_synthetic_fixture":false,"null_last_reviewed_at":null,"public_change_summary":"First indexed by Null; source disclosure date is shown separately.","null_first_observed_at":"2026-10-31T21:56:08.420Z"}],"next_cursor":null,"snapshot_revision":"42594"}