Authorities ID Mariposa Botnet Creator

The FBI announced Slovenian police have arrested the person accused of creating the malware behind the notorious Mariposa botnet.

Law enforcement officials have identified and arrested the person they said is the mind behind one of the largest botnets on the Web.

According to the FBI, the Slovenian Criminal Police identified and arrested a 23-year-old known as "Iserdo," who stands accused of creating malware known as "Butterfly Bot" that was used to build the Mariposa botnet. Mariposa is believed to have infected between 8 million and 12 million computers. The malware's target: credit card and bank account information, as well as passwords for Websites and financial institutions.

From 2008 to 2010, authorities allege Iserdo sold Butterfly Bot to cyber-criminals worldwide. In turn, these individuals developed networks of infected bots, of which Mariposa was the largest and most notorious, the FBI stated. In addition to selling Butterfly Bot, Iserdo developed customized versions for certain customers and created and sold plug-ins to augment the botnet's features and functionality.

The arrest follows three others by the Spanish Guardia Civil in February following a two-year investigation that also involved the FBI and the Slovenian Criminal Police.

"In the last two years, the software used to create the Mariposa botnet was sold to hundreds of other criminals, making it one of the most notorious in the world," said FBI Director Robert S. Mueller, III, in a statement. "These cyber intrusions, thefts, and frauds undermine the integrity of the Internet and the businesses that rely on it; they also threaten the privacy and pocketbooks of all who use the Internet."