Previously, Symantec had estimated that the Flashback botnet had the potential to earn hackers around more than $10,000 per day. "This could have been extremely profitable," said O Murchu.
O Murchu declined to estimate the current size of the Flashback botnet.
In many cases, Macs were infected by the Flashback malware via an exploit of a Java vulnerability that Apple was slow in patching on OS X 10.6, or Snow Leopard, and OS 10.7, aka Lion.
Since Flashback made headlines early in April, Apple has issued Java security updates for Snow Leopard and Lion, as well as a malware removal tool for those operating systems and OS X 10.5, better known as Leopard.
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, on Google+, or subscribe to Gregg's RSS feed. His e-mail address is firstname.lastname@example.org. See more articles by Gregg Keizer.
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