On Nov 12, two internet providers took down the servers for McColo Co. in San Jose, CA, after investigators identified McColo as originating 3 of every 4 spam emails worldwide.

http://www.washingtonpost.com/wp-dyn/content/article/2008/11/12/AR2008111200658.html

and

http://www.washingtonpost.com/wp-dyn/content/article/2008/11/19/AR2008111903075.html

I generally get anywhere from 500 to 1,200 spams a day at work depending on what's happening in Eastern Europe, and it takes a good 20 minutes for Outlook to come up when I turn on the computer. I did notice a precipitous drop in spams recently (when I came in on Monday, I had only 600 from over the weekend, which is unheard of). I joked that the credit crisis might be causing massive spammer layoffs, but I imagine it won't be long before spam finds some new server.

Posted at 12:05 AM ET, 11/26/2008
Spam Volumes Expected to Rise with Botnet Resurrection

Spam volumes could rise considerably over the next few days now that one of the world's largest networks of compromised computers used for blasting out junk e-mail was brought back to life tonight.

The "Srizbi" botnet, a collection of more than half a million hacked PCs that were responsible for relaying approximately 40 percent of all spam sent worldwide, was knocked offline two weeks ago due to pressure from the computer security community.

On Nov. 11, the Internet servers used to control the Srizbi botnet were disconnected when a Web hosting firm identified by security experts as a major host of organizations engaged in spam activity was taken offline by its Internet providers.

Turns out, Srizbi's authors had planned ahead for such a situation by building into each bot a fail-safe mechanism in case its master control servers were unavailable: A mathematical algorithm that generates a random but unique Web site domain name to check for new instructions and software updates.

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November 27, 2008 (IDG News Service) An Estonian ISP that temporarily hosted the command-and-control servers for the Srizbi botnet, responsible for a large portion of the world's spam, has cut off those servers, according to computer security analysts.

Starline Web Services, based in Estonia's capital Tallinn, had hosted four domain names identified as the control points for Srizbi, according to researchers from computer security firm FireEye.

Hundreds of thousands of PCs around the world infected with Srizbi, a difficult-to-remove rootkit that is used for sending spam, were programmed to seek new instructions from servers in those domains.

Srizbi is considered one of the more powerful botnets, with at least 450,000 PCs infected. It is estimated that half of the world's spam originated from computers infected with Srizbi. Spam remains a profitable business for cybercriminals.

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