Computer Viruses

In mid-July 2001, two variants of the Code Red worm began spreading through the Internet. Code Red operated in three stages -- scanning, flooding and sleeping. During the scanning phase, the worm searched for vulnerable computers and ran damaging computer code on them. Next, in the flooding phase, the worm sent bogus data packets to the White House Web site. The White House, however, changed their Web site's IP address and was therefore able to maintain computer security. Experts believed the worm's final sleep mode could last indefinitely, and that even infected machines would not pose a threat to the Internet. The worm also replaced Web site text with the phrase "hacked by Chinese." At its peak, the worm infected 2,000 machines every minute, and infected 359,000 machines and cost $1.2 billion. Because of a Code Red warning many people were able to protect their machines.