Ten Most Famous Computer Viruses in History

These days, there are far too many varieties of malware to name individually. At last estimate, over 560,000 new instances of malware are created every day, and a new victim succumbs to it every 14 seconds. Only the most significant and most impactful malware attacks are worthy of names, and even then, attacks occur so frequently that the names hardly sink into the public consciousness.

Anoymous hacker

For most of digital history, that wasn’t the case. Viruses have been around since the beginning of digital tech and have almost always warranted their name and plenty of public attention. Some attacks have become more famous than others, and they remain remembered and even revered by those in the cybersecurity field.


Perhaps the most famous computer virus of all time, ILOVEYOU, appeared on devices in a spam email with the subject line “I love you.”

Because malware was relatively unknown at the time, almost everyone who received the email became a victim, resulting in over $15 billion in damages to the system and personal files on over 10 million PCs.

2. MyDoom

Widely considered the most damaging virus ever deployed, MyDoom also ranks as the fastest-spreading email-based worm.

It is estimated that nearly one-quarter of all emails sent in 2004 contained copies of MyDoom, which used infected hosts to launch DDoS against Microsoft, Google, and other major tech firms.

3. Sasser & Netsky

These computer worms were created in 2004 by a 17-year-old German hacker trying to out-compete the MyDoom virus — which he very nearly did.

While Netsky spread far and wide, Sasser caused the most damage, resulting in the closure of Taiwan’s post offices, many branches of a Finnish bank, and the cancellation of various transatlantic flights.

4. Anna Kournikova

Anna Kournikova

Because tennis player Anna Kournikova was such a popular search term in the early 2000s, a hacker created a virus to capitalize on her popularity.

Sent as an attachment masquerading as a picture of Kournikova, the virus didn’t do much damage, but it did make its way onto machines around the world, resulting in the conviction of a 20-year-old who created it “as a joke.”

5. Zeus

Hackers created the Zeus virus in 2007 as a tool to assist in malware attacks on banks. Zeus came to develop a botnet or a system of machines that can be forced to work together to accomplish nefarious aims. Bits of the Zeus virus and the Zeus botnet is still at large today.

6. Slammer

A worm with an interesting attack strategy, 2003’s Slammer randomly selected computer IP addresses and found vulnerabilities to work its way onto machines across the internet.

Once it amassed a sizable number of devices, the worm launched a DDoS attack against various internet hosts, causing significant slow-downs in internet traffic and costing over $1.2 billion to fix.

7. WannaCry

In 2017, the WannaCry virus introduced ransomware to the world. Wreaking havoc in over 150 countries and crippling major social systems like public transit in Germany and the National Health Services in the U.K., WannaCry cumulatively cost over $4 billion to recover from.

8. Cryptolocker

Though WannaCry was the first famous ransomware, Cryptolocker was the first widespread, devastating ransomware. Launched in 2013, the virus was among the first major examples of malware creators encrypting files and demanding payment for the key. Versions of Cryptolocker still exist online, and users need to use antivirus protection to stay safe from known threats like these.

9. Code Red

Man in red mask

Code Red was a computer worm that debuted in 2001 and managed to wrack up about $2.4 billion in damages before disappearing from computers entirely.

At its peak, the worm launched a DDoS attack against the U.S. White House website, compelling the White House to change its IP address to survive.

10. Stuxnet

Developed by government engineers, Stuxnet is one of the most threatening viruses on this list because it can affect hardware and software. During its limited time globally, the virus caused Iranian uranium centrifuges to self-destruct, setting their nuclear development back significantly.

Stuxnet is an excellent example of a weapon for cyber warfare, which will likely increase as digital spaces become more dominant in the years to come.