Spam levels have reportedly dropped by as much as 70 percent in the two days after a web hosting firm used by criminals was dropped by its internet service providers. McColo lost its access after an investigation by the Washington Post.

IronPort, the same anti-spam company that revealed last month’s crackdown on a major spam gang made little difference to junk mail levels, says the quantity of spam it has measured is down significantly. Figures from another firm, Spamcop, show a smaller drop but also peg the dip as coinciding exactly with McColo going offline.

Unfortunately most experts believe the slowdown in spam will be short-lived. An IronPort spokesman told the BBC it is likely to be a temporary dip until the spammers find hosting in countries with less stringent regulation.

The Washington Post has now released data showing McColo was hosting sites for spam networks which averaged more than 75 percent of spam messages sent worldwide each day. The firm also hosted many of the bogus pharmacy sites where those who responded to the spam were invited to buy medicines, along with at least 40 child pornography sites.

McColo’s ISPs, Global Crossing and Hurricane Electric, pulled the plug after the Washington Post presented details of a four-month investigation. HostExploit, a group of volunteers from Google, McAfee and Arbor Networks, had also investigated McColo’s activities.

Whether McColo is guilty of any crime isn’t yet clear. Hosting firms generally don’t bear any legal responsibility for spam or sites selling bogus goods, but can face action over child porn content. A former Justice Department cyber crime prosecutor told the Washington Post that a hosting firm doesn’t have to have been aware of the content; if a court believes it reasonable to believe a firm should have been aware, it can still hold the firm legally responsible.

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Entry was posted on Thursday, November 13th, 2008 at 4:37 pm under Legal, Security, Spam.

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