Spam levels stable: Symantec

Stephen Withers
Tuesday, 30 June 2009 11:25

Business IT - Technology

Spam levels remain at 90 percent, according to security provider Symantec. But the situation would have worsened if a major botnet hadn't suffered downtime during June.

Symantec's MessageLabs Intelligence Report for June says that spam levels remain at the 90.4 percent figure seen in May.

83.2 percent of spam originated from botnets, so the downtime suffered by Cutwail in early June when the Pricewert ISP was shut down had a noticeable effect.

An estimated 1.5 to 2 million computers have been suborned into the Cutwail botnet, and according to Symantec officials was is responsible for 35 percent of all spam by the end of May.

According to Symantec's figures, no other botnet is responsible for more than 10 percent of spam.

Cutwail began to recover from the Pricewert shutdown within hours, and by late June was take to around one-third of its previous capacity. This was a much quicker recovery than that seen from Srizbi after the McColo shutdown.

"Cutwail's recovery to one-third of its original levels, after only a few hours, highlights the progress spammers have made since the McColo shutdown in November," said Paul Wood, MessageLabs Intelligence senior analyst, Symantec.

More on international spam levels on page 2.