Turning Back The ' Worm'

A new and potentially dangerous "worm" is attacking both servers and individual users. Symantec's Anti-Virus Research Center reports that "W32.Nimda.A@mm is a new mass-mailing worm that uses e-mail to propagate itself. The threat arrives as a file named readme.exe in an e-mail. Other anti-virus firms are also reporting the outbreak.

The worm appears to have the worst characteristics of the Code Red Virus that attacked Internet servers this summer, along with those of "I Love You," "Melissa" and other e-mail viruses that have plagued PC users for the past couple of years.

Individual and business users are affected because it spreads via Microsoft Outlook and Outlook Express through an attached file called Readme.exe. If you get an e-mail with that attachment, do not open it.

If you do, your computer could be infected and then could spread the worm to people on your address list. It won't destroy files on your PC, but the mere fact that you are sending it out and receiving it, means that it can slow down your system and have an effect on the Internet as a whole. It can also affect security by opening your C drive as a network "share," according to Symantec

In addition, this worm also affects web servers running Microsoft IIS software -- the same software that was affected by Code Red by exploiting a flaw in IIS called "Unicode Directory Traversal exploit."

When it infects a server, it not only slows down the server and puts unnecessary traffic on the Internet, it can also deface the server and spread itself even further by making it possible to visitors of the site to download a copy of the virus which, in turn, can infect their PC, according to a Symantec spokesman.

Anti-virus companies are in the process of providing updates. PC users should use the update mechanism built into their anti-virus software immediately.

Tips to Protect Yourself Against Viruses:

• Get an anti-virus protection for your computer. Update it frequently and set the options to scan e-mail as well as other files.
• Don't open any attachment if you are not expecting it, even if it is from people you know, unless you are certain that it's a legitimate file. If you're not certain, ask the sender to confirm that he or she sent you an attachment. Even then, there is a chance that the file could be infected.
• Backup your data often (and keep a backup copy in a different location in case of fire).
• Only download software from reputable sources.
• If you have a cable modem, DSL line or other full-time Internet connection, be sure you have a good firewall. ZoneAlarm offers an excellent free program for personal use.

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