Microsoft has freed two million computers from a series of major botnets operated by cybercrime gangs, which allowed them to steal $500 million (£319 million) from bank accounts across the globe.
The operation, conducted by the software giant and the FBI, occurred earlier this month across 80 countries, with the aid of national authorities.
1,400 computer networks that made up the Citadel botnets were seized and taken offline, disrupting the heart of the network. While some command and control servers are believed to still be online, Microsoft said it is confident it got most of the machines it was after.
“We definitely have liberated at least 2 million PCs globally,” said Richard Domingues Boscovich, assistant general counsel at Microsoft's Digital Crimes Unit, according to Reuters. “That is a conservative estimate.”
The main hacker behind the botnets, who goes by the name Aquabox, is still at large, but authorities are working to identify him and others. They believe he is living in Eastern Europe.
Microsoft claims that the Citadel network of botnets was able to grow through pirated versions of Windows, which came secretly bundled with the malware.
Citadel is particularly nasty, because it disables antivirus software, which makes it difficult to identify and remove.