writes "A big MS Windows remote vulnerability has just hit BugTraq. It concerns a buffer overflow in MS' DCOM, and affects Win2k through Server 2003; here's the security advisory from Microsoft. This is in addition to an earlier vulnerability concerning conversion from HTML to RTF - there's a separate security advisory from Microsoft for this one, and it affects Win98 and NT 4.0 through Server 2003. Patch early, patch often."
There's also a CNET News story
with a little more explanation on the newest vulnerability.