Blaster Worm attempts a Denial of Service on the Microsoft Windows Web server. This attempt is to prevent the user from applying a windows patch on your PC against the DCOM RPC vulnerability. The W32.Blaster.Worm will then exploit the DCOM RPC vulnerability via TCP port 135. Blaster Worm will then attempt to download the file msblast.exe to the windowscomputer32 directory then execute.