The Klez virus has become one of the most prolific viruses floating around on the internet. pcworld.com calls it a blended threat because it's distributed like a virus, sometimes behaving like a worm while other times acting like a Trojan horse.
Here's how it works: a victim receives an infected e-mail and clicks the attachment or previews the message. Klez then copies itself to the victim's hard drive, infects random files, and looks for e-mail addresses to send itself to, and--more importantly--disabling anti-virus software. Klez then propagates itself out through shared resources and e-mail. On the 6th of odd numbered months, it sends itself out again and corrupts files a week later on the 13th.
What can you do to prevent infection? Newer versions of anti-virus software do offer protection from Klez, so the ole saying "update your virus protection regularly" definitely applies. Same goes for security patches to IE and Outlook. And of course, spam protection software is good to have, too. If you're hard drive is infected, it can be difficult to clean up.
For this week in Geek, I'm Mark Avery.