Arbitrary file deletion via quarantine path race

A TOCTOU race in the quarantine process of Avast and AVG AntiVirus 22.5 through 22.10 allows local users to delete arbitrary files. AvastSvc checks a malware path for links, then deletes it later as SYSTEM; an oplock and swapped junction can redirect that deletion. Exploitation requires low-privileged local access and control of the quarantined file's parent path, enabling deletion of files or directories accessible to the service.