Microsoft .NET Framework 1.1 SP1 2.0 SP2 3.5 3.5.1 4 4.5 and 4.5.1 does not properly determine TCP connection states which allows remote attackers to cause a denial of service (ASP.NET daemon hang) via crafted HTTP requests that trigger persistent resource consumption for a (1) stale or (2) closed connection as exploited in the wild in February 2014 aka \POST Request DoS Vulnerability.\