Browsing histories published online in Kenzero virus scam

Users of the Winny filesharing service are thought to be particularly at risk from the Kenzero virus, which originated in Japan.

The Trojan virus is hidden inside some video files of explicit Hentai anime, which are shared across the Winny network. Once an unsuspecting computer user has downloaded the video file to their machine, the virus executes, popping up an installation screen that prompts the computer user to type in personal information.

The virus then takes screengrabs of a user's browsing history, and publishes a list of all the sites they have visited online. A dialog box or email is then sent to the user, demanding a credit card payment of around £10 to remove the list from the internet.

"We've seen the name before in association with the Zeus and Koobface Trojans," Rik Ferguson, a security adviser at Trend Micro, told the BBC. "It is an established criminal gang that is continuously involved in this sort of activity."

Computer users have been advised to ensure their antivirus, firewall and security software is up to date, and that they have downloaded any security patches for their operating system. Users who receive emails or dialog boxes demanding payment to settle alleged copyright infringement or for the removal of browsing histories are advised to ignore the demands, and instead to use an anti-malware scanner to check for suspicious files on their PC.