The Windows NAT Driver (aka winnat) service in Microsoft Windows Server 2012 does not properly validate memory addresses during the processing of ICMP packets, which allows remote attackers to cause a denial of service (memory corruption and system hang) via crafted packets, aka "Windows NAT Denial of Service Vulnerability."
Improper Restriction of Operations within the Bounds of a Memory Buffer The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary.