The SMB Server service in Microsoft Windows XP SP2 and SP3, Windows Server 2003 SP2, Windows Vista SP1 and SP2, Windows Server 2008 Gold, SP2, R2, and R2 SP1, and Windows 7 Gold and SP1 does not properly validate fields in SMB requests, which allows remote attackers to execute arbitrary code via a malformed request in a (1) SMBv1 or (2) SMBv2 packet, aka "SMB Transaction Parsing Vulnerability."