The Flashback malware that’s infected hundreds of thousands of Macs may be generating more than US$10,000 a day for the hackers who made the Trojan horse, according to the security specialist company, Symantec. The malware steals clicks from ads that Google’s search engine displays alongside search results.

In a blog post ( Symantec said that botnet measuring in the region of 25,000 infections could generate the author up to $450 per day. Considering the Flashback Trojan measures in the hundreds of thousands, this figure could sharply rise to the order of $10,000 per day.

The Flashback ad-clicking component is loaded into Chrome, Firefox, and Safari where it can intercept all GET and POST requests from the browser. Flashback specifically targets search queries made on Google and, depending on the search query, may redirect users to another page of the attacker’s choosing, where they receive revenue from the click . (Google never receives the intended ad click.)