Trends New Botnets Surpass Storm and Mega-D By Desmond Liao | 2 minute read According to a report by Marshal Threat Research and Content Engineering (TRACE) team, “Storm” and “Mega-D” are no longer the leading spam botnets. Recent months have shown a shift away from stock pumping, towards spam promoting branded pharmaceuticals such as erectile dysfunction (impotence) and weight loss products. The two largest botnets account for 61 per cent of all spam volume. Worthy of note, the size of a botnet doesn’t determine the amount of spam being distributed. Another key finding was that spammers’ experimentation in 2007 with spam laced in PDF, Word and MP3 attachments appears to have gone away for now. Overloads caused by botnets is a major concern for administrators who rely soley on content filtering. The real arms race is one of sheer volume between the amount of traffic spammers can send and the volume of traffic administrators can successfully deliver. Effective filtering software does nothing to decrease volume (they only separate spam from good email). So, the more email volume servers receive, the more hardware needs to be scaled to match. Traffic shaping on SMTP, as part of a multi-tiered anti-spam architecture, reduces overall volume and gives filtering software additional time to catch up and process emails. Not to mention, it restricts the bandwidth and resources botnets need to hammer your mail servers, dropping volume immediately and keeping spam entirely off your network.