10 Most Disruptive Computer Viruses in Internet History

Each year, US businesses and citizens lose billions upon billions of dollars due to the destruction caused by computer viruses. We’re all familiar with that sinking feeling when the first signs show — your browser freezes, your system slows, error messages pop up repeatedly, and bizarre antivirus software you never installed “scans” your computer. In worst case scenarios, it can spread to other computers, erase your hard drive, and ruin your machine altogether. A problem that predates the internet, the first virus was created 40 years ago, setting forth a problem that has grown with our dependence on computers. The following bugs are among the worst in history, and have caused many businesses and people to seek some form of insurance just in case.

1. Elk Cloner (1982): A first of its kind, the Elk Cloner didn’t harm a lot of computers, but it did set an unsettling precedent as the first wild virus, one that can freely spread on its own. Created by Richard Skrenta, a computer savvy high school prankster, it merely infected boot sectors, featuring a threatening message that read “It will get on all your disks. It will infiltrate your chips. Yes it’s Cloner!” Fittingly, Skrenta is now a computer programmer and Silicon Valley entrepreneur with extensive experience in the industry.
2. Brain (1986): Viruses were made more complicated and resilient with the formation of Brain, the first full-stealth virus capable of evading early disk utility programs. Infecting floppy disks, it caused only minor problems, as it slowed the disks and sometimes made them unusable. Brain originated in Lahore, Pakistan and its effects surfaced in 1987 and 1988, when infections were discovered at the University of Delaware and the Providence Journal-Bulletin, the latter of which experienced the deletion of work as a result. Today’s viruses that refuse to die are all grandchildren of Brain, which is why it will forever be considered among the most disruptive — it bred them.
3. Morris Worm (1988): The sanctity of the Internet was breached with the proliferation of the Morris Worm, which garnered mainstream attention because it resulted in the first US conviction under the 1986 Computer Fraud and Abuse Act. By attacking vulnerabilities in Unix sendmail, finger and rhs/rexec multiple times, it could cause programs to become unusable. Approximately 6,000 UNIX systems were infected by it, a disruption that couldn’t be ignored. Creator Robert Tappan Morris, a student at Cornell University, was convicted and sentenced to three years probation, 400 hours of community service, and given a $10,000 fine. Currently, the former outlaw is a tenured professor at MIT.
4. CIH Virus (1998): As the internet was rapidly expanding in the late ’90s, the first truly feared viruses emerged. The CIH virus did the most damage, as it overwrote critical information in system drives and corrupted system BIOS. Present in several thousand IBM Aptivas, it first surfaced on a large scale in Asia — it was created in Taiwan by Chen Ing-Hau — destroying numerous PCs. Measures of protection were implemented, but the virus returned in varying forms in the early 2000s.
5. Melissa (1999): Named after a lap dancer who creator David Smith met in Florida, Melissa rose to fame after it infected numerous mail systems, essentially shutting them down. When it arrived in inboxes, the message was titled “Important Message From [account sending the virus]” and contained an attachment with a list of 80 porn sites. Most disconcerting was its ability to send other documents that could’ve held sensitive information. For the trouble he caused, Smith served 20 months in a federal prison and paid a $5,000 fine.
6. ILOVEYOU (2000): The desire to be loved might explain why so many people opened those pesky emails with the subject line of “ILOVEYOU.” Readers were enticed to open the attachment titled “LOVE-LETTER-FOR-YOU.TXT.vbs” that appeared to be sent from someone they knew, causing the spamming of contacts in their address books and changes to their systems. Tens of millions of computers were infected and $8.75 billion in damage resulted. Onel A. de Guzman, a student of AMA Computer University in Makati, Philippines, admitted to being the culprit, claiming that he accidently discharged the virus.
7. CodeRed (2001): The aptly named CodeRed virus originated in the Philippines and featured the memorable text string “Hacked by Chinese,” exploiting indexing software in Microsoft’s Internet Information Server (IIS). Because it ran entirely on memory, infected computers’ hard drives were erased. Estimated to have affected one to two million people, CodeRed caused $2.75 billion in damage and even received the attention of the FBI, which classified it as worthy of crippling the entire internet.
8. Blaster Worm (2003): Microsoft was compelled to offer a cash reward to people who provided information leading to the capture of the creator of Blaster, a worm that launched a denial of service attack on the company’s website. Damage totaled $320 million, and, unfortunately for the many who dealt with it, the culprit was never found. One can only image the wrath he’d face given the punishment levied on the creator of the B variant, 18-year-old Jeffrey Lee Parson, who was sentenced to 18 months in prison in 2005.
9. MyDoom (2004): According to some sources, MyDoom is the most destructive and costly worm in the history of the Internet, causing $38.5 billion in damage and effecting 20 to 30 percent of worldwide email traffic. Rapidly spread through email and the popular file sharing application Kazaa, it presented itself as a transmission error and spread to other emails by prompting readers to open its attachment. As with the Blaster Worm episode, the creator of MyDoom wasn’t found, but some have speculated that he or she was paid and lived in Russia.
10. Conflicker (2007): If you’ve contracted a virus in recent years that presented itself as antivirus software, then it may have been Conflicker. Its purpose is to steal personal information from the owner of the infected computer, sticking around by disabling already existing, legitimate antivirus software. At one point, it controlled more than seven million computers worldwide, with several different variants that served to strengthen the original. The authors are still unknown, and are said to be tracking anti-malware developments designed to eradicate it.

Taken From Business Insurance