filelock is a platform-independent file lock for Python. From 4.1.0 until 4.2.1, SoftReadWriteLock and AsyncSoftReadWriteLock cache a successful check of the <path>.rw lock tree and resolve its names again during later record operations, allowing another local user who can replace that tree after the first acquisition to redirect lock-record writes into directories writable by the lock user. This issue is fixed in version 4.2.1.
https://github.com/tox-dev/filelock/security/advisories/GHSA-wfhq-q4j2-c37m
https://github.com/tox-dev/filelock/releases/tag/4.2.1
https://github.com/tox-dev/filelock/pull/842
https://github.com/tox-dev/filelock/commit/bfa066d65a1ba9106f86ee9d027f7588b9c77e03