Revision Note: V3.0 (June 10, 2014): Revised advisory to rerelease the 2862973 update for Windows 8 and Windows Server 2012. This rerelease only applies to systems running Windows Embedded 8 and Windows Server 2012 for Embedded Systems. See the Advisory FAQ for more information.Summary: Microsoft is announcing the availability of an update for supported editions of Windows Vista, Windows Server 2008, Windows 7, Windows Server 2008 R2, Windows 8, Windows Server 2012, and Windows RT that restricts the use of certificates with MD5 hashes. This restriction is limited to certificates issued under roots in the Microsoft root certificate program. Usage of MD5 hash algorithm in certificates could allow an attacker to spoof content, perform phishing attacks, or perform man-in-the-middle attacks.