** DISPUTED ** Race condition in F-Secure Internet Security 2010 10.00 build 246 on Windows XP allows local users to bypass kernel-mode hook handlers and execute dangerous code that would otherwise be blocked by a handler but not blocked by signature-based malware detection via certain user-space memory changes during hook-handler execution aka an argument-switch attack or a KHOBE attack. NOTE: this issue is disputed by some third parties because it is a flaw in a protection mechanism for situations where a crafted program has already begun to execute.