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 mishandle LDAP authentication, which allows man-in-the-middle attackers to gain privileges by modifying group-policy update data within a domain-controller data stream, aka "Group Policy Elevation of Privilege Vulnerability."