After a two-year international investigation, Slovenian police have arrested the suspected creator of the Mariposa botnet, which is estimated to have infected as many as 12 million computers.
The FBI on Wednesday announced the arrest last week by Slovenian Criminal Police of a 23-year-old Slovenian man known as "Iserdo." Authorities did not release his full or real name. He is suspected of creating the "Butterfly Bot" malware that was used to build the Mariposa botnet, which Spanish authorities shut down late last year.
Iserdo allegedly sold the Butterfly Bot to other criminals, who developed networks of infected computers, and also developed customized versions and sold plug-ins to boost the botnet's functionality.
According to the FBI, the botnet was used to steal passwords for financial institutions and websites, steal credit card and bank account information, launch denial of service attacks, and infect computers.
"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," FBI Director Robert Mueller said in a prepared statement.
Three suspected Mariposa operators were arrested in February by Spanish authorities: Florencio Carro Ruiz, Jonathan Pazos Rivera, and Juan Jose Bellido Rios.
The Mariposa investigation was a cooperative effort between the FBI and Slovenian and Spanish law enforcement.