The hacker believed to have created the infamous Mariposa botnet has gone on trial in Slovenia, charged with having masterminded an international cybercrime gang.
The 26-year-old Matjaž Škorjanc, also known as Iserdo, was arrested as part of an international intelligence sting.
At its height, the Mariposa botnet infected up to 12.7 million PCs, with more than half of the Fortune 1,000 companies believed to have been compromised, including 40 major banks.
One group of Mariposa botnet herders were arrested in Spain in March 2010. However the three men picked up by the Spanish authorities were believed to have bought the code from another group, as none of them possessed the programming skills necessary to develop the malware.
FBI officials worked with Spanish and Slovenian authorities to track down Mariposa's mastermind, Iserdo.
He was said to charge between $500 for basic versions of the botnet code and up to $1,300 for more advanced ones, which included customised features, such as capabilities which allowed its operators to to steal credit cards and online banking credentials.
The code was even found to have infected 3,000 HTC handsets shipped by mobile operator Vodafone.
The police unleashed the crackdown campaign against Mariposa in December 2009, when its command and control operations were targeted.
Škorjanc's former girlfriend Nuša Čoh is also reported to be facing charges of conspiring to launder money, according the Slovenian Press Agency.
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