Microsoft » Windows 7 : Security Vulnerabilities, CVEs, Published In November 2011 (Overflow)

Integer overflow in the TCP/IP implementation in Microsoft Windows Vista SP2, Windows Server 2008 SP2, R2, and R2 SP1, and Windows 7 Gold and SP1 allows remote attackers to execute arbitrary code by sending a sequence of crafted UDP packets to a closed port, aka "Reference Counter Overflow Vulnerability."