Antivirus company Avast alleges that ads served by companies such as Google, Yahoo! and Fox, and published on websites such as the New York Times and TechCrunch, have included bad software that could infect your computer.Users don’t even have to click the ads to be affected. Their browser gets infected just from loading the ads. CNet has the story.
Prontexi is a Trojan horse targeting Windows machines that looks for further vulnerabilities in software such as Adobe’s Reader and Acrobat, Java, QuickTime and Flash. It pops up fake antivirus warnings to trick you into installing further malware. The malware started spreading in late December. Since then, Avast has found it has infected more than 2.6 million computers. Almost 530,000 of those were from Yield Manager and more than 16,300 from DoubleClick.
The worst affected are Yahoo!’s Yield Manager, Fox Audience Network’s Firmserve.com and Google’s DoubleClick. Together, these networks serve over 50% of all internet ads. DoubleClick has been the least affected and Google has been the fastest at tackling the problem, according to CNet and Avast.