The Russian antivirus company said Thursday thatare behind 90 percent of malicious code, leaving teenagers and script kiddies responsible for only a small fraction of the rest.
"There's a lot of money in the Internet," said Eugene Kaspersky, head of antivirus research for Kaspersky Labs. "On the last count of malware I did, only 10 percent was written by teenagers. Ninety percent is developed by criminals. This malware is designed for criminal needs such as stealing money, distributing spam and Internet rackets."
FBI Deputy Assistant Director Steve Martinez warned last month that Eastern European gangs were turning increasingly to cybercrime. He said the FBI had urged law enforcement agencies in other countries to go after the gangs.
Criminals are turning to the Internet because of the lack of security and policing, Kaspersky said. "It's getting more serious because many attacks are being developed by professionals," he said. "It's not such good news because they have brains, and they are getting more experienced."
Kaspersky warned that Trojan horses, which open back doors on computers for hackers to enter through, have become easy to develop and are being used to steal banking details. Such Trojans wait for a user to browse a Web site with the word "bank" in it, he said. At that point, the Trojan records the user's key strokes, capturing their user name, password and account numbers.
Kaspersky highlighted the Brazilian hackers who were arrested earlier this year. Between them, the hackers stole around $80 million from Brazilian users, which Kaspersky said was a simple task. "I see this is a very good business," he said. "It's easy to attack Internet banks."
He added that press reports of the hackers' success had worked as an incentive for more hackers to try the same thing. "Now we have more Trojans (aimed at Brazilian users). This is a criminal business, and it works."
Zombie networks of computers, known as, are available to buy over the Internet, Kaspersky claimed. "There was a Web page with one for sale--an Internet shop for zombie networks, with 5,000 machines for $300."
Dan Ilett of London-based ZDNet UK reported from Moscow.