The Storm has dramatically calmed this April, with a MessageLabs report claiming that the Storm botnet was now only at five per cent of its original size.
Storm had been estimated at having compromised two million computers, but there was a 57 per cent decrease in malware-laden emails distributed by the Storm botnet during April.
MessageLabs suggested that the introduction of new malicious software tools which aimed to target and remove Storm infections may have been responsible. Microsoft's Malicious Software Removal Tool had recently been updated for this purpose.
But it wasn't all good news, as the same report said that web-based malware had increased by 23 per cent, with cyber criminals taking advantage of users unfamiliar with the web threat.
Analysis showed that 36.1 per cent of interceptions in April were new, with an average or 1,214 new websites per day harbouring malware, spyware or adware. This was an increase of 619 per day compared to March.
"April was a month of unpredictability with the mighty Storm botnet losing all but five per cent of its anonymous army and web-based malware reaching new levels," said Mark Sunner, chief security analyst at MessageLabs.
The report said that a new botnet called Srizbi, which showed up in 2007, had the potential to overtake Storm as the most notorious botnet.
Of the new threats, Sunner said: "This month we find ourselves fighting the cybercrime battle on many fronts, with the bad guys using an arsenal of weapons in order to detonate spam, viruses, phishing attacks and targeted Trojans."
In the week of the 30th anniversary of the first spam message, MessageLabs also reported on a new spamming technique which was being used to send authenticated spam email through Yahoo SMTP servers.
It accounted for one per cent of all spam intercepted in April, advertising services for Canadian Pharmacy, which the company said were well known for spamming.
It used the SMTP server and a DomainKeys Identified Mail (DKIM) authentication technique which ensured that the email was harder to block.
