Criminal-to-criminal transactions are disturbing Estonia

A senior Estonian official recently said for the first time that the cyber attacks earlier this year against his country's government and commercial Internet infrastructure were carried out using a network of computers infected with special hacker software that had been rented from a criminal syndicate.

Jaak Aaviksoo, the Estonian minister of defense, told a Washington audience last month that the botnet that attacked Estonia was "rented for that purpose and rented (from) clearly illegal groups that have hijacked a number of computers worldwide."Earlier this year a so-called bot-herder -- a hacker who had created several networks of infected computers for use by cyber-criminals -- pled guilty to federal wire-tapping crimes in a precedent-setting prosecution.

But commentators say that law enforcement agencies worldwide are falling behind the criminal syndicates, who hawk their wares -- including botnets for rent and bundles of stolen credit card or login information -- using anonymous instant messaging, chat rooms and online cash accounts like e-gold and WebMoney.

One company indicted by U.S. prosecutors allegedly was responsible for more than $4 million worth of credit card fraud and trafficked in nearly 100,000 stolen credit card numbers.