In the early 2000s, the FBI and other law enforcement agencies pretty much dismantled the U.S. cyber criminal underground, said Tom Kellermann, chief cybersecurity officer at Trend Micro, but it's made a resurgence in the past three years and there are now more participants than there were in 2000.
"It's larger because it's providing a wider multiplicity of goods and services," Kellermann said. "They're there for the drugs, weapons, passports, stolen cards, and murder for hire. It's a one-stop shop for criminals to facilitate their conspiracies, to bypass traditional security, and to launder money."
Drugs are the hottest commodity, accounting for 62 percent of all sites. Stolen data dumps account for 16 percent of all sites, fake documents for 4 percent, and weapons for 2 percent. Murder for hire sites account for 1 percent of the North American underground sites, according to Trend Micro.
Read more: US cyber criminal underground a shopping free-for-all