Top 10 Most Famous Computer Hacks in History

In November 2014, a hacker group calling themselves the 'Guardians of Peace' infiltrated Sony's computer infrastructure and leaked a trove of confidential data. The breach exposed personal information about Sony Pictures employees and their families, email conversations between staff, executive salary details, and unreleased movie copies. This cyberattack followed a previous hack in August 2014 that took Sony's Playstation Network offline. One member of the GOP hacking group claimed responsibility, stating they had accessed Sony's network for at least a year before the breach was discovered in November 2014. U.S. investigators found that the attackers spent months copying key files. It was believed that the hackers, allegedly linked to North Korea, were retaliating over the planned release of the movie *The Interview* in 2014.

In 2014, the popular online auction and shopping platform eBay was rocked by a major security breach that exposed sensitive data of approximately 145 million users. This included encrypted passwords, names, addresses, birthdates, and other personal details. At the time, it was the largest cyberattack ever carried out against a corporation. Thankfully, eBay had kept financial records (like credit card information) in a separate, secure database, which was not affected. To mitigate the damage, the company required all 145 million users to reset their passwords.

The breach also posed a risk of further theft across other sites. Hackers may have been able to decrypt passwords with automated software, giving them access to thousands of popular services, including social media, online banking, and email accounts. The key takeaway: segregating databases can be a lifesaver in the event of a breach. Always ensure security measures match the sensitivity of the data you store.

In March 2013, the anti-spam service Spamhaus was hit with the largest Distributed Denial of Service (DDoS) attack in history. The attackers used nearly 100,000 servers to generate up to 300 gigabits per second (Gbps) of traffic, overwhelming large portions of the internet. The attack's scale was massive, and its impact was felt across the web, affecting sites like Netflix. To put the size of the attack into perspective, a typical DDoS attack creates 4-10 Gbps of traffic. According to Spain's Ministry of the Interior, the suspect used a van outfitted with multiple antennas to scan frequencies like a mobile command center, enabling him to access networks from virtually anywhere in the country. Reports also indicated that the suspect operated from a "bunker" in northern Spain, separate from another one in the Netherlands.

Stuxnet was a highly sophisticated computer worm first discovered in 2010, designed primarily to target Iran's nuclear facilities. Over time, it evolved and spread to other industries, including energy production. The worm specifically attacked programmable logic controllers (PLCs) that were used to automate industrial processes. Stuxnet garnered widespread attention due to its unprecedented ability to damage hardware, marking the first known instance of malware capable of physically destroying equipment. It was suspected to have been developed by the U.S. National Security Agency (NSA), the CIA, and Israeli intelligence agencies.

Many rumors suggested that Stuxnet was a joint cyber weapon developed by the U.S. and Israel. The worm spread via infected USB drives, infiltrating computers within isolated networks not connected to the internet. It famously disabled numerous uranium-enriching centrifuges at Iran's Natanz facility by causing them to malfunction. Over time, other hackers adapted Stuxnet to target facilities such as water treatment plants, power stations, and natural gas pipelines.

Conficker is a notorious computer worm that targeted Microsoft Windows operating systems, infecting millions of computers across governments, businesses, and households in over 190 countries. It became infamous for its resilience and the ever-changing strategies it employed to spread and update itself. Discovered in November 2008, Conficker, also known as Downadup, created a botnet infrastructure and spread rapidly. Once it infected a system, it disabled security features, deleted system restore points, and opened backdoors to receive commands from remote computers.

The worm was designed to communicate with control machines, and experts feared it might initiate further attacks on April 1st. Some speculated that cybercriminals would rent portions of the botnet to carry out spam, identity theft, phishing, and other malicious activities. The origin of Conficker remains unknown to this day, although members of the Black Hat 2009 conference suggested Ukraine as a possible source.

The biggest hack to date was actually a series of attacks that spanned over 8 years. A group of hackers from Russia and Ukraine targeted U.S. banks and companies, stealing 160 million credit and debit card numbers while also breaching 800,000 bank accounts. This became the largest known cybercrime case and credit card breach in history, with victims including Nasdaq, 7-11, JC Penney, and JetBlue.

Beginning in 2005, brands and systems like 7-Eleven and JC Penney were repeatedly attacked by this Russian hacker group. Over the span of 7-8 years, the breach led to the loss of over 800,000 bank accounts, 160 million credit and debit card details, and various other datasets. It's believed that these hackers caused at least $300 million in global damages. Some of the stolen data was sold on the dark web (with credit card numbers going for $10-50 each), while other information was used to directly withdraw money from accounts—an estimated $9 million was taken using fake ATM cards at Citibank and PNC Bank.

In late March 1999, a programmer named David Lee Smith hijacked an America Online (AOL) account and used it to post a file to an internet group called “alt.sex”. The file promised to provide dozens of free passwords for adult websites. When users clicked to download the file and opened it in Microsoft Word, a virus was unleashed on their computers. By March 26, the virus had spread rapidly across the internet.

The Melissa Virus was a macro virus that sent out mass emails with an attachment. When opened, it would disable security features in Word 97 or Word 2000. If the user had Microsoft Outlook, the virus would then forward itself to the first 50 contacts in the user’s address book. Computer programmer David L. Smith was sentenced to ten years in prison (of which he served 20 months). He also paid a $5,000 fine for his role in creating and spreading the virus, which caused $80 million in damages. The FBI and New Jersey State Police launched an investigation after the virus crippled computers and networks in both business and government sectors.

In May 2017, a devastating ransomware attack crippled the NHS, affecting up to 40 hospitals and trust organizations. The attack disrupted operations, canceled appointments, and diverted ambulances. The WannaCry ransomware locked access to critical health records, with hackers demanding a $300 ransom in Bitcoin per affected user.

Regarded as one of the largest ransomware attacks in history, it infected 57,000 computers in the UK alone. The attack spread across 99 other countries, compromising over 140,000 machines. According to the National Audit Office, 19,500 patient appointments were canceled, 600 GP surgery computers were locked, and 5 hospitals had to reroute ambulances. The self-propagating nature of the virus meant that some areas of the NHS were hit far harder than others. Northern and Midlands & East regions saw 32 out of 37 NHS trust organizations affected, simply because they were the first to be attacked, allowing the virus to spread quickly across their networks.

In February 2016, unidentified cybercriminals launched a major attack on a Bangladesh central bank official’s computer. This became one of the largest cyber heists in history, with $81 million stolen and funneled into the Philippines. According to Bangladesh Ambassador John Gomes, the hackers were not from either the Philippines or Bangladesh. The criminals sent fraudulent messages to the Federal Reserve Bank of New York in an attempt to transfer nearly $1 billion from Bangladesh's central bank.

The hackers succeeded in transferring $81 million through four separate transactions to Rizal Commercial Banking Corporation in the Philippines, and another $20 million to Pan Asia Banking in a single request. However, the Bangladesh Bank was able to halt $850 million in other transfers. The $81 million was sent to four accounts at a Rizal branch in Manila on February 4, 2016. These accounts had been opened a year earlier, in May 2015, with only $500 in them. A printer malfunction alerted the Bangladesh Bank to the theft.

TalkTalk was targeted not once, but twice. In 2015, the company suffered a massive data breach, compromising the personal and banking details of up to four million customers. These details were then placed in a spreadsheet and held for ransom. The breach cost TalkTalk an estimated £42 million. As a result, 101,000 customers were left, and the company was fined £400,000 by the Information Commissioner’s Office for failing to adequately protect personal data. The attack affected TalkTalk’s profits and customer base.

In 2016, TalkTalk’s routers became the target of another cyberattack involving malware. A 17-year-old hacker confessed to his involvement in the 2015 breach and received a 12-month rehabilitation order, along with the confiscation of his smartphone and hard drive. This new attack resulted in hundreds of thousands of customers losing Internet access after their Wi-Fi passwords were stolen from the routers. Following the breach, TalkTalk’s stock price took a hit, and the company continues to feel the impact. In an effort to recover, the company is attempting a major relaunch with new branding, packages, and a renewed focus on customer security.