Think of it as a digital white-out attack.
Microsoft is investigating a quirk in Internet Explorer 4.0 that lets a Java applet paint the computer desktop or any active window white.
The applet only works when IE 4.0 is used with Microsoft's Active Desktop, which lets users place Web-based images and applets, such as .gifs or stock tickers, on the desktop.
Users are affected only if they visit a Web site where the applet has been planted intentionally.
"The Active Desktop has two layers," said IE product manager Craig Beilinson. "There's the icon layer, with the familiar desktop icons, and the HTML layer, which lets you add Web stuff to the desktop. While we are still investigating this issue, it seems as if this Java applet is simply painting white pixels on top of the HTML layer."
"It's more of a nuisance than anything else," he added. "Nobody's been hurt by this thing and nobody will be."
Beilinson said Microsoft was still looking for a solution to the problem. He noted that users currently could hit the "control," "alt," and "delete" keys simultaneously, which will enable them to close IE and get rid of the problem.