Double free vulnerability in the Ancillary Function Driver (AFD) in afd.sys in the kernel-mode drivers in Microsoft Windows Server 2003 SP2, Windows Vista SP2, Windows Server 2008 SP2 and R2 SP1, Windows 7 SP1, Windows 8, Windows 8.1, Windows Server 2012 Gold and R2, and Windows RT Gold and 8.1 allows local users to gain privileges via a crafted application, aka "Ancillary Function Driver Elevation of Privilege Vulnerability."