Microsoft Windows 2000 SP4, XP SP2 and SP3, Server 2003 SP2, Vista Gold, SP1, and SP2, and Server 2008 Gold and SP2 allow remote attackers to cause a denial of service (TCP outage) via a series of TCP sessions that have pending data and a (1) small or (2) zero receive window size, and remain in the FIN-WAIT-1 or FIN-WAIT-2 state indefinitely, aka "TCP/IP Orphaned Connections Vulnerability."