Kerberos 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, 1511, and 1607 allows man-in-the-middle attackers to bypass authentication via vectors related to a fallback to NTLM authentication during a domain account password change, aka “Kerberos Elevation of Privilege Vulnerability.”