Winsrv.dll in the Client/Server Run-time Subsystem (aka CSRSS) in the Win32 subsystem in Microsoft Windows XP SP2 and SP3, Windows Server 2003 SP2, Windows Vista SP2, Windows Server 2008 SP2, R2, and R2 SP1, and Windows 7 Gold and SP1 does not properly check permissions for sending inter-process device-event messages from low-integrity processes to high-integrity processes, which allows local users to gain privileges via a crafted application, aka "CSRSS Vulnerability."