An Indian web publisher claims a Trojan program that replaces Google ads with a different set of ads has been found in the wild.
A report on the TechShout website said a Trojan affecting AdSense has been discovered. Google has not confirmed this yet on the AdSense blog, but a web publisher named Raoul Bangera is said to have contacted Google about the problem.
Google reportedly confirmed the information provided by Bangera, including screenshots, logfiles, and system files, demonstrated the ads displayed on his site were not legitimate.
"We can confirm from the screenshots that these are fake Google ads, formatted to look like legitimate ads. We agree that this phenomenon is likely the result of malicious software installed on your computer," Google reportedly said in response.
"Most of the ads were about gambling or adult content, which are banned categories in Google AdSense, clearly indicating a suspicious origin," Bangera said in the report. Only small publishers appear to be affected, not premium publishers or Google sites.
Site publishers should review their ads, and report any unusual ones like ads that violate Google's terms of service to Google for follow-up.