Microsoft and Symantec have shut down a massive click fraud botnet known as Bamital, numerous variants of which have been in circulation since 2009 amassing several million dollars in fraudulent profit for the attackers as well as spreading more malware including scareware.

The botnet thrived on hijacking clicks on targeted search engine results pages, Symantec said. Clicks on ads and malicious links were redirected to the attacker’s server, which correlates the search phrase and where the click came from to redirect the victim.