There are few details on why it is releasing the patch, but a little research shows that it is a flaw in SMB - Windows File Sharing. The update will be released at 10 A.M. Pacific time, as announced on the Microsoft Security blog.
If you take a peek over at the National Vulnerability Database, we can see this article Here is the overview:
Buffer underflow in Microsoft Windows 2000 SP4, XP SP2 and SP3, Server 2003 SP1 and SP2, Vista Gold and SP1, and Server 2008 allows remote attackers to execute arbitrary code via a Server Message Block (SMB) request that contains a filename with a crafted length, aka "SMB Buffer Underflow Vulnerability."
This means this vulnerability could be exploited to create a worm. Further it means if one PC gets infected on your network, then quickly all of them will.
After doing some more research it seems there is already an exploit in the wild - it is set to "go off" during the Thanksgiving holiday here in the states.
This is a very serious vulnerability and I suggest making sure your computers are updated with the patch as soon as possible.
Posted By: Steve Wiseman on Thursday, October 23, 2008
Check out our utilities for windows