"When a user tries to play a protected Windows media file, this technology demands a valid license. If the license is not stored on the computer, the application will look for it on the Internet, so that the user can acquire it directly or buy it," Panda Software explained.

An unsuspecting user attempting to download the DRM (digital rights management) license will instead be redirected to a Web site that loads a large quantity of adware, spyware, modem dialers and other viruses, the company said in an advisory.

"It's pretty ingenious," said Patrick Hinojasa, chief technical officer at Panda Software. "To take an anti-piracy feature and use it to feed spyware is extremely ironic."

Ironic, perhaps. Inevitable, for sure.