The SMB Server in Microsoft Windows Vista SP1 and SP2, Windows Server 2008 Gold, SP2, and R2, and Windows 7 does not properly validate an internal variable in an SMB packet, which allows remote attackers to cause a denial of service (system hang) via a crafted (1) SMBv1 or (2) SMBv2 packet, aka "SMB Variable Validation Vulnerability."
Improper Input Validation The product receives input or data, but it does
not validate or incorrectly validates that the input has the
properties that are required to process the data safely and
correctly.