Organized viruses and organized crime

After the Melissa virus struck in 1999, e-mail-borne viruses peaked the following year with ILOVEYOU, which clogged e-mail servers worldwide within 5 hours.

As e-mail spam filters improved to block bulk mailings, malicious coders looked elsewhere, turning to self-propagating worms like MSBlast, which exploited a flaw in Remote Procedure Call messages, and Sasser, which exploited a flaw in Internet Information Services (IIS). About this time, viruses and worms began using Simple Mail Transfer Protocol (SMTP) to bypass e-mail filters so that the compromised machines could spew pharmaceutical spam to random addresses on the Net.

Shortly after Microsoft's Reward program netted Sven Jaschen, author of Netsky and Sasser, in 2004, the image of a single author creating viruses in a parents' basement fell out of favor, replaced by organized crime operations with financial ties to porn and bulk pharmaceutical companies. (In 2005, PCWorld wrote a series on the problem, "Web of Crime.") Groups such as the Russian Business Network (RBN) ran sophisticated spam campaigns, including pump-and-dump penny-stock spam.

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