Sandy Bird, chief technology officer for Q1 Labs, examines the possibility of Instant Messaging (IM) worms. IM has become commonplace; it is included in Windows installations by default, and portable devices, such as phone and PDAs (personal digital assistants) also have IM technology. An IM worm could use this to spread quickly but silently. After an IM worm infects a computer, it can access the IM buddy list, see which buddies are online, and pass the infection to them. It can also keep track of its infections. This would eliminate the traffic floods that accompany other worms. Such worms could also access user profiles and past conversations to tailor social engineering attacks. Many organizations have banned IM traffic from their networks, but employees can IM over HTTP (hypertext transfer protocol) and encryption can prevent effective filtering.
http://news.com.com/2010-7355-5163671.html?tag=nefd_gutspro

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