A Danish member of the StopBadware discussion group has highlighted a disturbing outbreak of ad-driven malware on the websites of Danish media companies over the past several days. Cometcom1 posted that within several days, the affected websites were cleaned up, but that the owners of the affected sites seem unwilling to admit their share of responsibility, laying all blame squarely on the ad networks themselves. A lively debate on the ethics of using advertising online ensued.

Cometcom1 reports that there has now been a second round of infection hitting different Danish media sites, leading some users to avoid all media sites and some companies to block media sites preemptively from their networks.

At StopBadware, we feel that both website owners and advertising networks have a shared responsibility to ensure the safety of internet users. While ads are generally hosted remotely, an ad shown on a site is as much a part of that site as its other content. As with any third-party content, we caution website owners to choose carefully what they allow onto their sites.