The Unreal engine, as used in Unreal Tournament 3 1.3, Unreal Tournament 2003 and 2004, Dead Man's Hand, Pariah, WarPath, Postal2, and Shadow Ops, allows remote authenticated users to cause a denial of service (server exit) via multiple file downloads from the server, which triggers an assertion failure when the Closing flag in UnChan.cpp is set.
Unreal engine 3, as used in Unreal Tournament 3 1.3, Frontlines: Fuel of War 1.1.1, and other products, allows remote attackers to cause a denial of service (server exit) via a packet with a large length value that triggers a memory allocation failure.