W32.Topion.B is a worm affecting all versions of the Microsoft WIndows operating system. The worm spreads by copying itself to all removable drives on infected computers.
Once a computer is infected with the worm it will copy itself to “Explorer.exe”. The worm also creates various registry keys to run the program at startup. It can also lower security settings and change file extensions.
The worm will copy itself to all removable drives as well as adding autorun files to the removable drives.