The Hyper-V server implementation in Microsoft Windows Server 2008 Gold, SP2, and R2 on the x64 platform allows guest OS users to cause a denial of service (host OS hang) via a crafted application that executes a malformed series of machine instructions, aka "Hyper-V Instruction Set 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.