Virus writers have crafted a malware threat that serves up expensive Google AdSense web pages related to mesothelioma, a rare cancer caused by exposure to asbestos.
Industry workers affected by the disease have launched a series of lawsuits, a factor that means "ambulance chasing" lawyers pay through the nose to get a mention when searches for the term "mesothelioma" are made. The cost-per-click for the term "mesothelioma" is among the highest in the online ads business ranging from $4 to $13 and higher on various keyword bidding networks.
This, in turn, makes the term a prime target for click-fraud. Google AdSense allows online publishers to make revenue by displaying Google ads relevant to the content of their site. Because Google pays the host Web site based on the number of clicks on their ads, the process can be susceptible to "click-fraud".
The KMeth worm, which targets Yahoo! Messenger users, directs infected users to a web site serving a barrage of Google AdSense advertisements related to mesothelioma. Financially-motivated malware writers apparently hope to cash on the ruse through shares in the resulting advertising commissions which we doubt will materialise. Fraud detection mechanisms employed by Google are more than likely to identify rogue sites generating suspiciously high returns using such illicit tactics but that doesn't eliminate the other security risks consumers face from the worm.
KMeth exploits IE vulnerabilities to infect surfers who visit malware infested sites controlled by hackers, promoted through IM messages sent to the Yahoo! Messenger contacts of infected users. The "status message" in Yahoo! Messenger can also be also hijacked, presenting potentially enticing messages to their contacts, such as "check out my blog" in order to trick potential marks into becoming infected, IM security firm FaceTime reports.
Meanwhile an infected user's IM control panel is disabled, and their home page is hijacked to point towards rogue web sites designed to generate maximum revenue through click fraud. Using malware to perpetrate click-fraud is an established technique but the KMeth worm extends this idea by employing a battery of social engineering techniques.
"Typically, financially-driven malware attacks use botnets to fraudulently increase traffic to specific online advertisements," said Chris Boyd, director of malware research for FaceTime Security Labs. "In this case, the hackers have cleverly borrowed tactics from botnet-creators to create a bot-less network of hijacked PC users to drive traffic to sites populated with these specific Google AdSense advertisements. Introducing the human factor into the scenario makes these 'bot-less nets' much more difficult to detect."
A full write-up of the threat can be found on FaceTime's security research blog here. ®