Viruses and other malware usually spread by email, or through web servers. They are increasingly transmitted through instant messaging. There are about two or three attempts every month to spread viruses this way. Each one has limited distribution, to 50,000 or so recipients.
IM is quite attractive as a vehicle for malware, because once you’re in the client, it’s quick to grab the buddy list and then send files onward.
The distribution rate is growing at around 100% every six months. So malware-via-IM isn’t a major headache yet, and hopefully won’t be for the next two years. But longer term, it’s a communications channel that will need to be protected.
IMlogic’s Threat Center announced this week is a nice illustration of the type of technique the industry will need to adopt.