W32.Blaster.Worm is a worm that exploits the DCOM RPC vulnerability (described in Microsoft Security Bulletin MS03-026) using TCP port 135. This worm attempts to download and run the Msblast.exe file.
The worm also attempts to perform a Denial of Service (DoS) on Windows Update. This is an attempt to prevent you from applying a patch on your computer against the DCOM RPC vulnerability.
Removal using the W32.Blaster.Worm Removal Tool Symantec Security Response has developed a removal tool to clean infections of W32.Blaster.Worm. This is the easiest way to remove this threat and should be tried first.