Visitors to the 27-year-old socialite's website, ParisHilton.com, risk having sensitive personal information stolen from their computers. The virus prompts users to download software to enhance viewing of the site. However, whether they click 'yes' or 'no' on the pop-up, the site attempts to download a malicious Trojan program from another infected website. Users were greeted with a pop-up box that informed them they needed to "update" their systems, according to web security firm ScanSafe, which first reported the infection on Monday. The dialogue box gave users the option to choose "cancel" or "OK," but any click downloaded.

According to Landesman, there's an iFrame that has been embedded in the ParisHilton.com Web site. The iFrame calls out to a site hosting the malware, you69tube.com. It downloads a malicious PDF and attempts to force users into clicking and launching the PDF, which attempts to activate an exploit. Because the malware tries to download additional files whether one clicks "Cancel" or "OK," Landesman says that only a hard quit -- CTRL+ALT+Delete -- of one's browser provides a way out. It's not clear which exploits get launched. "These exploit frameworks generally include a cocktail of potential compromises," said Landesman. "The exploit being used appears to have been patched in November, but that has not been confirmed." She said it wasn't clear how the iFrame got added to Paris Hilton's site, but she said it could be because of a vulnerability in the open source content management system Joomla, which has been a common factor in other reports.