One Month After McColo Takedown, Spam on the Rise Again

As many readers are probably aware, a little less than one month ago, the email security world saw that most rare of occurances -- a drop in spam volumes. This was precipitated by the takedown of "bad guy" hosting service McColo.

Just as surprising, after dropping to about 60% of the volume before McColo was taken offline, spam volumes stayed fairly constant for a couple of weeks before slowly starting rise (see chart at left). Rises in "spam" reported by some other email vendors during this period were likely misinterpretations of legitimate bulk email, which always rises during November as retailers and even enterprise vendors increase the volume of direct email they send promoting holiday deals and end-of-year events.

The Proofpoint Attack Response Center now reports that spam volumes are starting to rise more rapidly again. We started seing this acceleration at the very end of November. Looks like control of various botnets that send spam has been re-established. Currently, spam volumes are down about 35% from the high levels right before the McColo takedown. Click the graphic to take a closer look...