Null pointer dereference

The RPC Marshalling Engine (aka NDR) in Microsoft Windows 2000 SP4, XP SP2 and SP3, Server 2003 SP2, Vista Gold, SP1, and SP2, and Server 2008 SP2 does not properly maintain its internal state, which allows remote attackers to overwrite arbitrary memory locations via a crafted RPC message that triggers incorrect pointer reading, related to “IDL interfaces containing a non-conformant varying array” and FC_SMVARRAY, FC_LGVARRAY, FC_VARIABLE_REPEAT, and FC_VARIABLE_OFFSET, aka “RPC Marshalling Engine Vulnerability.”