Nimda
loresecurity
The September 2001 worm that attacked through five vectors at once, a week after 9/11.
Released on September 18, 2001, Nimda (admin backwards) spread by email, open network shares, defaced websites that infected their visitors, IIS exploits, and the backdoors left by Code Red II, becoming the Internet's most widespread worm within hours. Arriving days after the attacks on New York, it triggered brief fears of cyberterrorism that analysis never supported. It taught defenders that malware need not choose a single door.