Microsoft Security Advisory MS01-043 - The NNTP service in Windows NT 4.0 and Windows 2000 contains a memory leak in a routine that processes news postings. Each time such a posting is processed that contains a particular construction, the memory leak causes a small amount of memory to no longer be available for use. If an attacker sent a large number of posts, the server memory could be depleted to the point of crashing. Microsoft FAQ on this issue available here.
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