The font mapper in win32k.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 does not properly scale fonts, which allows local users to cause a denial of service (system hang) via a crafted application, aka "Windows Font Driver Denial of Service Vulnerability."