McColo, an ISP suspected of aiding cybercriminals in online scams and hosting child pornography has been at least partially disconnected from the Internet.
ISPs can connect with each other to exchange Internet traffic, a practice known as "peering." Hurricane Electric, an ISP that was one of the primary connections for McColo's traffic, has disconnected with McColo, one of a handful of so-called "bulletproof" hosting providers that provide a safe haven online for cybercriminals.
Global Crossing, an IP (Internet Protocol) network services provider also connected to McColo would not comment, however McColo's main website remains offline.
The shutdown coincides with a damming new report on McColo authored by several computer security researchers who detail how McColo and other questionable service providers are linked to spam and cybercrime.
McColo's shutdown "demonstrates that when presented with appropriate evidence of criminal activity, the Internet community can bring about the positive forces necessary to purge it," the analysts wrote.
McColo, whose servers were located within the US, at one time hosted up to 40 websites with child pornography, the report said.
McColo also played a big role in spam distribution, said Richard Cox, CIO of Spamhaus, which tracks spamming operations. It hosted websites that could infect people's computers with malicious software used for sending spam, he said.
Hacked computers then become part of a botnet, or networks of PCs that can be used to send spam or attack other websites.
McColo hosted the so-called command-and-control servers for botnets that are used to instruct PCs to send spam. The botnets included Rustock, Srizbi, Pushdo/Cutwail, Ozdok/Mega-D and Gheg, according to the report.
When it received complaints, McColo would shift around the suspect websites on its network and try to erase traces of wrongdoing, Cox said.
"Essentially, a lot of these providers know what their customers are doing and try to protect them," Cox said.
Analysts are predicting a drop in spam and botnet activity while McColo is offline. Joe Stewart, director of malware research for SecureWorks, said on Wednesday that he'd received only one spam message from the Rustock botnet, while on a normal day he might get up to 20.
McColo's demise is going "to be kind of a vindication for a lot of researchers that have been complaining about McColo for years and why law enforcement wasn't doing anything about it," Stewart said.
SecureWorks has tracked bad activity at McColo, but law enforcement has always been "tight-lipped" about investigations, he said.
But it may only be mere days before those who use hosting services from McColo find other bulletproof hosters. "There's all kinds of wanna-be McColos that are on the hacker forums, the spammer forums," Stewart said.
In fact, bad activity at McColo increased after the shutdown in September of Intercage, a California hosting company also known as Atrivo, Cox said. Intercage's upstream providers stopped carrying its traffic following years of complaints that the ISP supported spam and harmful websites.
McColo's increased activity showed spammers just moved from Intercage to there, and will likely move fast, Cox said. Cybercriminals probably have "hot stand-by" websites ready to go with other service providers to stay in business, Cox said.