According to AVG, the website for antivirus vendor AvSoft Technologies has been hacked, resulting in a virus being installed on visitor's computers. The malware is being hosted in the site's download section.

"They let one of their pages get hit by an iFrame injection," Roger Thompson, AVG's chief research officer said. "It shows that anyone can be a victim. ... It's hard to protect Web servers properly."

The malware is a variant of the Virut virus family. Virut is known as a "parasitic infector" virus that is extremely difficult to remove.

"It infects all of your programs on your local hard drives, and then it starts hitting your network drives as well the first time you run," Thompson said.

No one is quite sure how the hack was accomplished as of yet.