13 Biggest Cyber Attacks in History

biggest cyber attacks in history
Credit: RoonZ nl

Cybersecurity is big business in today’s world of online connectivity. However, when hackers beat defenses, organizations, markets, and government infrastructure can be devastated. Some of the biggest cyber attacks in history have seen whole cities blacked out from coordinated cyber warfare, or millions of people’s private information leaked. 

A cyber attack can be carried out by anyone, from hacker groups to governments and organizations. Methods of cyber attacks include denial of service, ransomware, phishing, malware, viruses, and hacking. Most recently, AT&T suffered a nationwide outage last month, which is still being investigated, but impacted over 74,000 customers. Below are some of the biggest cyber attacks in history.

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13. Melissa Virus, 1999

Ed Hardie

12. Shamoon, 2012

Markus Spiske

11. Estonia, 2007


10. NASA, 1999


9. Adobe, 2013

Emily Bernal

8. Ukraine’s Power Grid, 2015

American Public Power Association

7. MOVEit, 2023

Markus Spiske

6. WannaCry Ransomware, 2017

Clint Patterson

5. Yahoo!, 2014

Markus Spiske

4. Bangladesh Bank Cyber Heist, 2016

Eduardo Soares

3. Triton, 2017

Marcin Jozwiak

2. Stuxnet, 2010

David Meyers

1. NotPetya, 2017 / Biggest Cyber Attacks in History

Tim Käbel

Alexandria is a News Editor, writer, and reader of all things literature. She graduated from the State University of... More about Alexandria Wyckoff