The RPC NDR Engine in Microsoft Windows Vista SP2, Windows Server 2008 SP2 and R2 SP1, Windows 7 SP1, Windows 8.1, Windows Server 2012 Gold and R2, Windows RT 8.1, and Windows 10 Gold and 1511 mishandles free operations, which allows remote attackers to execute arbitrary code via malformed RPC requests, aka "RPC Network Data Representation Engine Elevation of Privilege Vulnerability."