Kerberos in Microsoft Windows Vista SP2, Windows Server 2008 SP2 and R2 SP1, Windows 7 SP1, Windows 8, Windows 8.1, Windows Server 2012 Gold and R2, Windows RT Gold and 8.1, and Windows 10 Gold and 1511 mishandles password changes, which allows physically proximate attackers to bypass authentication, and conduct decryption attacks against certain BitLocker configurations, by connecting to an unintended Key Distribution Center (KDC), aka "Windows Kerberos Security Feature Bypass."