Risk: Informational
Virus writing has changed from a cottage industry to a commercial enterprise, according to anti-virus firms. A 51.8 percent increase in new viruses was reported for 2004.
Many of the 10,724 new viruses (up from 7,064 in 2003) surrendered control of infected PCs to virus writers, for use in distributing spam or launching DDoS attacks. The trend appears to be more about trying to generate money rather than creating mass mailing worms.
The increased prevalence of rogue dialler Trojans, which change victims’ net settings to dial expensive premium rate accounts, and the use of keylogging Trojans in phishing scams are examples of how virus writers can make money. Sophos estimates 40 percent of spam comes from infected computers, another way for malware authors to cash in.
2004 saw an upsurge in arrests of virus writers, most notably Sven Jaschan, the self-confessed author of the infamous NetSky and Sasser worms. The German teenager wrote his malware in a misguided attempt to remove spam-friendly viruses such as MyDoom from infected PCs. Instead he created a monster.
NetSky-P accounted for almost a quarter of virus incidents reported, topping the annual charts. Five NetSky variants also made it into the top 10. So Sven Jaschan was responsible for more than 50 percent of all virus incidents reported in 2004.
All of the top 2004 viruses only infect Windows PCs and most are still causing problems months after their initial discovery. Concerns about smartphone viruses are overhyped, with virus writers likely to continue targeting Windows PCs in 2005 and beyond. It is calculated that there are now 97,535 viruses in existence.