Global spam traffic rebounds as Rustock wakes

Spam is on the rise after the Rustock botnet awoke from its Christmas slumber, according to Symantec.

On Monday the Rustock botnet, responsible for a significant portion of the world's spam, resumed activity after pausing spam operations on 25 December.

"As Rustock has now returned, this means the overall level of spam has increased. MessageLabs Intelligence honeypot servers have seen an increase of roughly 98 percent in spam traffic between 00:00 and 10:00 today compared to the same period on 9 January," Symantec wrote on Monday. "It is too early to say what effect this will have on global spam levels, or if this return is permanent, but at the moment it certainly seems as if the holiday is over and it's now back to business as usual," it said.

Symantec noted that the botnet had not been entirely quiet over the Christmas and New Year period; it continued to commit click fraud, which involves manipulating infected computers into simulating a click on a web page advertisement, bringing revenue from advertisers.

Email security company Proofpoint's data concurs with Symantec's figures. "As if spam has returned to work from a long holiday break, volumes have been sharply rising this fine Monday morning to levels similar to those observed before the 12/25/10 'vacation'," Proofpoint said.