Number of spam emails increases dramatically

Spam levels soared last month and internet users can expect more of the same, according to Symantec.

The security software developer's monthly Messagelabs Intelligence Report found that in February spam increased by 5.5 per cent to 89.4 per cent of all emails. It said most of this was due to an increase in activity from the Grum and Rustock botnets.

The majority of spam was pharmaceutical related, which now accounts for 65 per cent of all spam, followed by watches and weight-loss scams.

Paul Wood, senior analyst with Messagelabs said: “Spammers have been using multiple botnets to distribute high-volume spam campaigns in February.

“Based on these latest spam patterns, we can predict additional surges in spam in the coming weeks.”

The number of phishing emails was also up and this type of email now accounts for more than half of all email-borne threats, the report found. However, the number of attachments was down, with only 0.56 per cent of spam containing one.

“Rather than attach images to emails directly,” Wood said, "spammers are choosing to host the image online with a free image hosting service, thus reducing the average file size of a spam email and enabling the botnets to send a greater volume of spam per minute.”