A botnet of more than four million infected computers has been shut down by a joint operation between the FBI and Estonian police, ending a scam that’s run for more than three years and taken an estimated $14 million from those affected in what’s been called “the biggest cybercriminal takedown in history.”
Computers in more than 100 countries were infected by the “DNSChanger” malware, which redirected searches for Apple’s iTunes store to fake pages pretending to offer Apple software for sale, as well as sending those searching for information on the U.S. Internal Revenue Service to accounting company H&R Block, which allegedly paid those behind the scam a fee for each visitor via a fake internet ad agency.
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The botnet apparently started in 2007, and was initially discovered by the space agency NASA, who had 130 computers infected by the scheme. Both PCs and Apple computers were susceptible to attack, and Trend Micro’s security blog has a guide for users to find out if their machines were part of that number.
Six Estonians were arrested as part of the joint FBI/Estonian police effort, Operation Ghost Click, with a seventh suspect, a Russian citizen, remaining on the loose.
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Graeme McMillan is a reporter at TIME. Find him on Twitter at @Graemem or on Facebook at Facebook/Graeme.McMillan. You can also continue the discussion on TIME’s Facebook page and on Twitter at @TIME.