Heap-based buffer overflow in the CRpcIoManagerServer::BuildContext function in msdtcprx.dll for Microsoft Distributed Transaction Coordinator (MSDTC) for Windows NT 4.0 and Windows 2000 SP2 and SP3 allows remote attackers to execute arbitrary code via a long fifth argument to the BuildContextW or BuildContext opcode, which triggers a bug in the NdrAllocate function, aka the MSDTC Invalid Memory Access Vulnerability.
The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.