The Top Computer Hacks of All Time

In today's world of the internet, life has become more comfortable with just a click. However, the internet is also a bane for your data's privacy and security. Be it for organizations or individuals, cyberattacks are dangerous, and they leave a lasting impact. In this article, I'll take you through ten of the top computer hacks of all time; here, you will be introduced and acquainted with the deadliest cyber attacks humankind has ever witnessed. 

Here’s a look at the top computer hacks that wrote history:

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10. Estonia (2007)

  • On April 27, 2007, Estonia, the European country, faced a series of cyberattacks that lasted for weeks. This happened when the Estonian government decided to move the Bronze Soldier from Tallinn's center to a less prominent military cemetery located on the city's outskirts. 
  • Unprecedented levels of internet traffic took down Estonian banks' online services, broadcasters, and government bodies. Botnets sent massive waves of spam, and vast amounts of automated online requests for deluged servers. It subjected the public to Distributed Denial of Service attacks.
  • Although there is no confirmation, Russia is believed to be behind these cyberattacks that largely crippled the Estonian society.

9. Ukraine Power Grid (2015)

  • On December 23, 2015, several parts of Ukraine witnessed a power outage. This was not a typical blackout, but the result of a cyberattack. It compromised the information systems of three energy distribution companies in Ukraine.
  •  It is the first victorious cyberattack on a power grid. Hackers sent out phishing emails to the power companies. 30 substations were switched off, and about 230,000 people were left in the dark for about 1 to 6 hours. 
  • U.S. investigators believed that Russia-based hackers were responsible for this. Experts have also warned that other countries could also be vulnerable to such attacks. 

8. NASA (1999)

  • In the year 1999, NASA computers were shut down for 21-days because of a cyberattack. The hacker was the then 15-year-old Jonathan James. He was the first person to carry out a computer hack against the American space agency.
  • He first penetrated a U.S. Department of Defense division's computers and installed a 'backdoor' on its servers.  
  • This allowed him to intercept more than a thousand government emails, including the ones containing usernames and passwords. This helped James steal a piece of NASA software and crack the NASA computers that support the international space station, which cost the space exploration agency $41,000 as it shut systems down for three weeks. 

7. Sony Pictures (2014)

  • In late November 2014, there was a leak of confidential data from the film studio in Sony Pictures. Data about Sony Pictures employees, their emails, copies of the then-unreleased Sony films, future propositions, and other crucial data were leaked. 
  • This attack was carried out by a hacker group named Guardians of Peace. In return, they demanded that Sony withdraw its then-upcoming film "The Interview". The movie was a comedy about a plot to assassinate the North Korean leader Kim Jong-un. Sony then decided to cancel the film's theatrical release because of the threats at cinemas screening the film.
  • It is hard to trace the roots of a cyberattack. In this case, after evaluation, the U.S. intelligence officials arrived at the theory that it related the attack to the government of North Korea; however, North Korea had denied the same.

6. TJX Security Breach (2006)

  • In Dec 2006, TJX, the U.S. retailer company, discovered that 45.6 million debit and credit card details were stolen from one of its systems. This happened over a period of more than 18 months by an unknown number of intruders. It was one of the first largest-ever cyberattacks involving the loss of personal data. 
  • This resulted in banks in the affected regions to reissue and block thousands of payment cards. A group of hackers carried out this cyberattack; Albert Gonzalez was the mastermind. This group was from Miami, the place where the TJX heist was believed to have originated.
  • Reports mentioned that the TJX data breach occurred because of weak WEP encryption at two of its Marshalls stores in Miami.

5. Stuxnet (2010)

  • 2010 witnessed the discovery of the deadly computer worm Stuxnet. Unlike other cyberattacks, Stuxnet aimed at destroying the equipment the computers controlled. Its purpose was to damage Iran's nuclear infrastructure. 
  • Stuxnet infected more than 200,000 computers, including 14 industrial sites and a uranium-enrichment plant in Iran. It mainly damaged the centrifuges of the Iranian reactors. It initially spread via Microsoft Windows and targeted Siemens industrial control systems. 
  • This was believed to be a cyber weapon created by the U.S. and Israeli intelligence. However, there is no documented evidence or acceptance by either of the countries for the same. 

4. Home Depot (2014)

  • In the year 2014, Home Depot was the victim of one of the most significant cyber attacks. It compromised 56 million payment cards, along with 53 million customer email addresses stolen. 
  • This transpired between April to September 2014. Hackers were believed to have used a third-party vendor's username and password to enter the perimeter of Home Depot's network. 
  • The attackers were then able to deploy custom-built malware on its self-checkout systems in the U.S. and Canada. 

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3. Sony Playstation (2011)

  • In April 2011, Sony executives witnessed abnormal activity on their PlayStation network. This resulted from a cyberattack wherein approximately 77 million PlayStation users' accounts were compromised and prevented users of PlayStation 3 and PlayStation Portable consoles from accessing the service.  
  • This resulted in Sony turning off the PlayStation Network on April 20. This lasted for 23 days. Sony released almost daily announcements concerning the system outage.
  • Sony is believed to have invested approximately $170 million to improve the network's security, to investigate the attack, and to cover the expenses of caring for the consumers that had been affected.

2. WannaCry Ransomware Attack (2017)

  • May 2017 witnessed one of the deadliest cyberattacks took place. It was the WannaCry ransomware attack, caused by the WannaCry crypto worm. The victims were the users who used the unsupported version of Microsoft Windows and those who hadn't installed the new security update. This happened through an exposed and vulnerable SMB port. 
  • The attack originated in Asia, and then eventually spread across the globe. In a day, more than 200,000 computers were infected across 150 countries. The WannaCry crypto worm locked the users out of the target systems and encrypted the data. In return, the victims were asked for a ransom of $300 - $600, which had to be paid via bitcoin. 
  • This attack resulted in billions of dollars of damage. Within a few days, the emergency patches released by Microsoft halted the attack, and the discovery of a kill switch prevented the infected computers from spreading the crypto worm. Security experts and a few countries believed that North Korea was behind this attack. 

1. Melissa Virus (1999)

  • More than 2 decades ago, in March 1999, The Melissa virus, a mass-mailing macro virus, was released. The target was Microsoft Word and the Outlook-based systems; the virus created considerable network traffic. It infected computers via Email. They sent a fake email that looked like an important message. If the recipient downloads the attached document and opens it with Microsoft Word, it unleashed the virus on their computers.
  • The virus would then mass-mail itself to the first 50 people in the victim's contact list. This began spreading like wildfire across the Internet. David L. Smith released the virus. This virus caused nearly $80 million worth of damages.
  • Surprisingly, there was no intention to steal data or money. However, it caused havoc; it disrupted almost 1 million email accounts worldwide. Some agencies were overloaded, and some had to be shut down entirely, and it slowed internet traffic in some locations down. This is one of the best computer hacks.

Those were the list of the top computer hacks of all time. 

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In this article, you have seen an overview of the top computer hacks in history. These were just a few of the deadly cyberattacks that have happened; the world has seen many more. Hence, it is of utmost importance to be careful while handling digital data and implement cybersecurity to put a curb on such cyberattacks. 

Today, cyber security is one of the top of the list of companies across industries. Business focus on this area has increased tremendously to build internal capabilities to proactively anticipate, tackle, and prevent such computer hacks and cyber attacks that can prove to be critically detrimental to the business. Cyber security professionals with the right skill sets are in high demand today, and companies are looking to provide solutions to safeguard business data and interests. Simplilearn’s Post Graduate Program in Cyber Security with modules from MIT College of Computing and EC Council offers professionals today an ideal launchpad to kickstart their cybersecurity career. In addition to getting a deep working understanding of today’s most effective cyber security best practices and techniques, including masterclasses from MIT College of Computing faculty, program learners get to perfect their skills with multiple assignments, 25+ projects, and a Capstone. To know more about computer courses.

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About the Author

Shruti MShruti M

Shruti is an engineer and a technophile. She works on several trending technologies. Her hobbies include reading, dancing and learning new languages. Currently, she is learning the Japanese language.

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