John says: More information on this is available
here

W32.Novarg.A@mm
is a mass-mailing worm that arrives as an attachment with the file extension
.bat, .cmd, .exe, .pif, .scr, or .zip.

When
a computer is infected, the worm will set up a backdoor into the system by opening
TCP ports 3127 through 3198, which can potentially allow an attacker to connect
to the computer and use it as a proxy to gain access to its network resources.

In
addition, the backdoor can download and execute arbitrary files.

The
worm will perform a Denial of Service (DoS) starting on February 1, 2004. It
also has a trigger date to stop spreading on February 12, 2004.