10 of the Worst Cyber Attacks in History

Cyber Attacks aren’t just a new concept, it’s been going on for decades, not just during the golden age of the Internet, but even before it’s modernisation for consumers. Here are 10 examples of the worst

  1. Michael Calce under the name MafiaBoy caused $1 billion dollars in damages in 2000 by unleashing a DDoS attack on a number of high profile commercial websites including Amazon, CNN, eBay and Yahoo! At the time, Yahoo! was a multibillion-dollar web company and the top search engine. [1a] Mafiaboy’s Rivolta managed to shut down Yahoo! for almost an hour. Today, Calce is now a white hat hacker. Companies hire him to help identify security flaws in their systems and design better security features. He says the internet is a far scarier place today than it was back in 2000. For one, there is more and more at stake as we rely ever more on online systems for our daily lives.


  1. The Melissa virus in 1999 targeted Microsoft Word, it was an e-mail attachment that would once open, forward the virus onto the first 50 users on Microsoft Outlook by Office’s native share function. [2a] This virus shut down multiple e-mail servers due to the wide spread attack, it cost $80 million in damages due to the virus acting like a Denial of Service attack to e-mail clients. Many people in the IT industry said that the situation could have been much worse, as what the virus really did was email itself. The Virus has multiple Simpson’s jokes hidden inside it. [2b]


  1. WannaCry was a ransomware attack in 2017 that had widespread success, hacking into organisations from the NHS to Telefonica and FedEx. It uses the EternalBlue exploit the US National Security Agency reportedly found in order to do its damage. It asks the user to pay fee of $300 in BitCoin to unlock the files. The ransom note indicates that the payment amount will be doubled after three days. [3a] If payment is not made after seven days it claims the encrypted files will be deleted. It’s estimated that WannaCry has caused $4 billion in damages so far and have earned up to $49,000 through BitCoin so far. [3b]


  1. TalkTalk was hacked by a 17 year old boy in 2015. The data breach was severe with customer sort codes and account number being made available. The firm said 4% of TalkTalk customers have sensitive data at risk. The attack cost the company £42 million and further had to pay £400,000 as they failed to have a secure system in place to avoid customer data breach. The attack was performed by two friends Matthew Hanley, 22, and Connor Allsopp, 20.[4a]


  1. In July 2015, and named as “The Impact Team” stole user data of Ashley Madison, a commercial website billed as enabling extramarital affairs. On 18 and 20 August, the group leaked more than 25 gigabytes of company data, including user details. The site’s policy of not deleting users’ personal information caused distress to many users as they feared being publicly shamed. [5a] This was the largest security breach of Consumer information in history. Impact Team wanted the owners of Ashley Madison (Avid Life Media) to remove the site due to the sites nature of encouraging affairs. [5b]


  1. In 2004, Sven Jaschan developed and released two damaging worms called NetSky and Sasser. At the time, they were responsible for over 25% of all virus reports in the first half of 2005. [6a] Sasser instead of attacking computer’s by e-mail. It would use a script to forward to an at risk computer and instruct it to download the script. Forwarding on and on. The system would also be difficult to shut down without unplugging the system manually. NetSky utilised e-mail to send files that would cause a Denial of Service attack as systems would collapse while trying to handle the data and traffic. These viruses caused over 20 billion dollars in damages. [6b & 6c]


  1. Sony suffered a massive blow to its Playstation Network in April 2011 after it was hacked by Anonymous via DDoS attacks. They attacked again on the 21st April 2011, and Sony kept the Network offline for 3 whole weeks. [7a] They were quiet about the reason for 5 whole days, when they announced that 77 million users personal information was compromised. Sony couldn’t rule out the possibility that Credit Card data wasn’t taken either. After apologising and reimbursing customers with free games, subscriptions and anti-fraud protection, Sony was left with a loss of £171 million. [7b]


  1. Prior to the internet, computers were being used for coding and creating different software. This was the case for a Canadian pipeline company in 1982. The CIA suspected the KGB might steal the software so they planted a logic bomb in the code, and a few months later, the Soviet pipeline exploded producing the most monumental non-nuclear explosion and fire ever seen from space. [8A] This is an instance of a Trojan horse before the widespread use of this method of virus occurred in the Personal Computing industry. Due to this attack, they only trust IBM an American manufacturer of computer chips to develop them. [8b]


  1. Albert Gonzalez was sentenced to 20 years in prison after hacking TJX the parent company of TJ Maxx (TK Maxx in the UK). He obtained 130 million records of personal information, including credit card information. He utilised backdoors on several systems to obtain the information. Once arrested the police seized multiple items he paid for with the information, such as $1.6 million ($1.1 million of which was in plastic bags buried in a three foot drum under his parents backyard.) [9a], multiple top of the range laptops, and a compact Glock pistol [9b].


  1. The Shamoon virus targeted computers and workstations of energy suppliers. It was developed in 2012 by a hacker group by the name “Cutting Swords of Justice” with the aim of destabilising the Saudi Amarco Company. They were successful and managed to infect more than 30,000 workstations, this prevented machines from connecting to the network that gave workstations access of communicating with each other and the web. The virus even infected Qatari RasGas Company and LNG Company. [10a]

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1a) https://en.wikipedia.org/wiki/MafiaBoy & Davis, Wall. Crime and the Internet. New York: Routledge, 2001.

2a) http://www.pandasecurity.com/mediacenter/malware/most-famous-virus-history-melissa/

2b) https://nakedsecurity.sophos.com/2009/03/26/memories-melissa-virus/

3a) https://www.symantec.com/connect/blogs/wannacry-3

3b) http://uk.businessinsider.com/wannacry-ransomware-attack-49000-3-bitcoin-wallets-2017-5

4a) http://www.bbc.co.uk/news/business-34743185

5a) http://www.ibtimes.co.uk/ashley-madison-hack-who-are-impact-team-why-did-they-leak-website-data-will-they-be-caught-1516328

5b) https://www.reddit.com/r/AnythingGoesNews/comments/3h71ar/we_are_the_impact_team_we_are_releasing_the/

6a) https://www.sophos.com/en-us/press-office/press-releases/2005/07/va_sasserfree.aspx

6b) http://virus.wikia.com/wiki/Sasser

6c) http://virus.wikia.com/wiki/Netsky

7a) http://www.eurogamer.net/articles/2016-04-26-sony-admitted-the-great-psn-hack-five-years-ago-today

7b) https://www.theregister.co.uk/2011/05/24/sony_playstation_breach_costs/

8a) http://www.telegraph.co.uk/news/worldnews/northamerica/usa/1455559/CIA-plot-led-to-huge-blast-in-Siberian-gas-pipeline.html

8b) http://www.nytimes.com/2009/10/27/science/27trojan.html?_r=1&ref=science&pagewanted=all

9a) http://www.cbsnews.com/news/soupnazi-with-1m-buried-in-backyard-pleads-guilty-to-biggest-hack-in-us-history/

9b) http://www.nydailynews.com/news/world/soupnazi-hacker-albert-gonzalez-nerdy-life-sex-guns-drugs-article-1.394977

10a) http://www.nytimes.com/2012/12/10/business/global/saudi-aramco-says-hackers-took-aim-at-its-production.html

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