A recently discovered botnet has been caught siphoning ad revenue away from Google, Yahoo! and Bing and funneling it to smaller networks.
According to researchers at Click Forensics, computers that are part of the so-called Bahama Botnet are infected with malware that sends them to counterfeit search pages instead of the real thing. They look authentic, and with the help of DNS poisoning routines, they even display google.com yahoo.com or bing.com in the address bar.
But the search results returned by these bogus sites have been ginned in some significant ways. While links contained in the organic results ultimately lead to a real site, browsers are first redirected to a series of ad networks that receive a small referral fee. Sponsored links, which typically pay the real search engine each time they are clicked, have also been jury rigged so a smaller ad network gets paid instead.
“The idea is to make money through click fraud,” said Matt Graham, a risk analyst at Click Forensics that provides auditing services to advertisers. “When those people actually do searches, that’s when these guys can display these ads hidden in the organic search results.”
Source: The Register