spam-inducing worms, like SoBig, which became threatening enough that Microsoft even offered a $250,000 bounty for information leading to the arrest of its creator.
8) Slammer (2003) In January 2003, the fast-spreading Slammer proved that an Internet worm could disrupt private and public services, a harbinger for future mayhem. Slammer works by releasing a deluge of network packets, units of data transmitted over the Internet, bringing the Internet on many servers to a near screeching halt. Through a classic denial of service attack, Slammer had a quite real effect on key services. Among its list of victims: Bank of America’s ATMs, a 911 emergency response system in Washington State, and perhaps most disturbingly, a nuclear plant in Ohio.
9) Code Red (2001) Compared to modern malware, Code Red seems like an almost kinder, gentler version of a threat. But when it swept across computers worldwide in 2001, it caught security experts off guard by exploiting a flaw in Microsoft Internet Information Server. That allowed the worm to deface and take down some websites. Perhaps most memorably, Code Red successfully brought down the whitehouse.gov website and forced other government agencies to temporarily take down their own public websites as well. Though later worms have since overshadowed Code Red, it’s still remembered by anti-virus experts as a turning point for malware because of its rapid spread.
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