A History of the Worst Cyberattacks

In 2023 alone, there were 2,365 cyberattacks, which resulted in more than 343 million victims worldwide.

Cyberattacks aren’t new. Since the birth of the internet, organizations from all sectors have been targeted by cyber threats of all kinds.

In today’s digital age, however, cyberattacks have become even more of a looming threat for companies, big and small, leaving millions of individuals vulnerable to having their personal data compromised. When corporations are targeted, the repercussions can be monumental, often resulting in the exposure of sensitive information belonging to hundreds of millions of users. The aftermath of such breaches not only shakes consumer trust but can also cause stock prices to plummet and customers to abandon brands 

Businesses invest heavily in cybersecurity every year, striving to build robust defenses against potential threats. However, the battle between security experts and cybercriminals is ongoing. As companies develop more sophisticated security measures, hackers continuously evolve, crafting even more advanced techniques to bypass these defenses.

The relentless tug-of-war highlights the urgent need for companies to stay one step ahead in protecting their data and maintaining customer trust. Ultimately, this high-stakes game emphasizes the crucial role of vigilance and innovation in the realm of cybersecurity. 

Between an increase in cyber threats, a major skilling gap in the workplace, and the rapid adoption of new technology, cyberattacks look very different today than they did a few years ago. Therefore, individuals and organizations alike must understand what cybersecurity vulnerabilities look like amid the dynamic evolution of cyber threats.

Here are some of the most common types of cyberattacks individuals and organizations face today:

1. Malware: Malware is a type of software designed to wreak havoc on computer systems and disrupt users. Almost every modern cyberattack involves malware of some kind. Hackers use malware attacks to break into systems, making them inoperable, destroying data, stealing sensitive information, and even erasing crucial operating system files. One prevalent type of malware is ransomware, which takes control of a victim’s data or device and locks it, then demands a payment to unlock or prevent the stolen information from being leaked.

2. Phishing: Phishing is the most common type of cyberattack seen today. It most often comes in the form of fraudulent emails, email attachments, text messages, or phone calls to trick people into sharing personal data or login credentials, downloading malware, sending money, or taking other actions that could expose them to cybercrimes.  

3. Denial-of-service (DoS) Attacks: A denial-of-service attack is like a digital traffic jam. It’s when a website or system gets bombarded with so much fake traffic that it slows down or becomes completely unusable for legitimate users. Distributed denial-of-service attacks (DDoS), are similar except they use a network of internet-connected, malware-infected devices or bots to cripple or completely crash the targeted system.

4. Man-in-the-middle (MitM) Attacks: Man-in-the-middle attacks occur when cybercriminals sneak into network connections and secretly listen in and hijack conversations, stealing valuable data in the process. One common trick they use is to target people on unsecured Wi-Fi networks where they can easily intercept the information being sent between devices. It’s a stark reminder to always be cautious when connecting to public Wi-Fi.

5. Zero-day attacks: A zero-day attack is a sneaky type of cyberattack that exploits hidden or unpatched security weaknesses in software, hardware, or firmware. The term “zero-day” refers to the fact that a software or device vendor has “zero days” to fix the vulnerabilities because malicious actors can already use them to gain access to vulnerable systems, rendering these attacks particularly harmful because they leave systems exposed and unprotected before anyone even knows there’s a problem.

To truly grasp the gravity of cybersecurity, it is also essential to examine some of the most infamous cyberattacks that have occurred throughout history. These incidents not only illustrate the potential scale and impact of modern cyber threats but also underscore the critical importance of continuing to take robust cybersecurity measures today.

Here is a break-down of some of the worst cyberattacks in history: 

The Melissa Virus 

One of the earliest and biggest modern cyberattacks known today occurred in 1999 and is referred to as the Melissa Virus. The hacker responsible for the virus hijacked an America Online (AOL) account and used it to post a file on an internet newsgroup, promising dozens of free passwords to fee-based websites. When users took the bait, downloaded the document, and then opened it with Microsoft Word, a virus was released on their computers, taking over their Microsoft Word program and then hijacking the Microsoft Outlook email system. It then sent messages to the first 50 addresses in their mailing lists, therefore repeating the baiting cycle and operating like a malicious chain letter. 

While the virus didn’t steal any money or sensitive information, it wreaked lots of havoc. Overall, approximately one million email accounts were disrupted, and servers were overloaded at over 300 corporations and government agencies worldwide. 

At the time that the attack occurred, the Melissa virus was considered the fastest-spreading infection, awakening many Americans to the dark side of the web. Importantly, the virus also served as an example to spread awareness of the danger of phishing attacks and opening unsolicited email attachments, bringing awareness to the new reality of online viruses and the damage they can cause. 

The NASA Cyber Attack

A few months after the Melissa Virus, between August and October of 1999, a 15-year-old hacker caused a 21-day shutdown of NASA computers after he used a vulnerability in the operating system to gain unauthorized access to NASA’s computer system. The attack resulted in the hacker being able to invade a Pentagon weapons computer system and intercept over 3,000 emails to steal important usernames and passwords, also resulting in a $41,000 cost in contractor labor and replaced equipment for NASA. 

This attack was a significant event in the history of cybersecurity as it was one of the first high-profile cyberattacks against a government agency, and it highlighted the vulnerability of even the most secure computer systems. As a result of the attack, NASA and other government agencies increased their security measures, highlighting the danger of cyberattacks and the need for better cybersecurity practices.  

The Sony PlayStation Network Outage

In 2011, the Sony PlayStation Network encountered a major incident in which the names, addresses, dates of birth, passwords, and financial details such as credit and debit card information of about 77 million people with accounts on its PlayStation Network were leaked. The intrusion was potentially one of the biggest ever into a store of credit cards. 

In response to the attack, Sony PlayStation Network took several measures to enhance its security and prevent future incidents, including temporarily shutting down the PlayStation Network and rebuilding the network with stronger infrastructure. 

Yahoo Data Breach

Affecting more than three billion people, the Yahoo cyberattack in 2013 is considered to be the largest data breach in history. The sheer scale of the breach is staggering and it resulted in the hackers gaining access to extremely sensitive information such as names, dates of birth, addresses, and passwords which could be used to commit identity theft or break into other accounts held by the same users. This breach had a major impact on the internet giant and its customers, resulting in various lawsuits and financial liability for the company.

The hackers were allegedly able to gain access to Yahoo’s system through a single click on a spear phishing email. That’s why cybersecurity training regarding phishing and other cyber threats is crucial for businesses and needs to be taken seriously by companies of all sizes.

WannaCry Ransomware Attack 

The WannaCry ransomware attack was a major security incident that impacted businesses and organizations all over the world. In May 2017, the WannaCry ransomware worm encrypted data on victims’ computers and demanded a ransom payment to decrypt the data. The attack affected more than 200,000 computers in 150 countries, and it was especially dangerous because it spread quickly thanks to a feature that allowed it to move from one computer to another. Notable attack victims include FedEx and the UK’s National Health Service (NHS).

Within hours of the attack, the spread of the virus was temporarily neutralized, thanks to a cybersecurity expert who discovered a “kill switch” that turned off the malware. However, many affected computers remained encrypted and unusable until the victims paid the ransom or could reverse the encryption.

The Equifax Data Breach

In 2017, the world saw another major attack when hackers stole a trove of financial data from Equifax, a top credit-reporting company. This breach potentially exposed the personal information of as many as 143 million people. Information stolen during the breach included customer names, credit card numbers, Social Security numbers, birthdates, and addresses.

This attack was especially pertinent as Equifax is one of the three major companies that monitor credit scores after data breaches, with companies like Target, Home Depot, and Sony having used Equifax’s credit monitoring services. Given the wide range of financial or other institutions that report credit details to Equifax, many of the 143 million consumers affected by the breach may not have even been aware that the company was storing their information, rendering the attack especially troubling. 

The Log4j Vulnerability

The Log4j vulnerability is a critical vulnerability that was discovered in the Apache Log4j library in 2021. Since Log4j is one of the most widely deployed open source programs in the world, many security agencies have considered the vulnerability to be extremely catastrophic. 

While Apache was able to respond to the vulnerability and limit some of the ways hackers could take advantage of it, it is still an ongoing issue that is predicted to continue affecting hundreds of millions of devices for years to come. Because no single action can completely fix the issue, organizations have to continuously stay aware of the dangers of the Log4j vulnerability and instill security measures through which to best protect their data and information.

The MOVEit Cyberattack

In 2023, the biggest attack of the year involved the widely used file transfer software MOVEit. Mass exploitation of a zero-day vulnerability allowed cybercriminals to steal data from a large array of businesses and governments. The full extent of the attack was unknown in the few months immediately following the breach, but ultimately, around 2,620 organizations and 77.2 million people were affected. 

The MOVEit incident revealed the importance of organizations ensuring the safety and security of their supply chains in addition to internal security, considering that several of the organizations impacted were not direct users of the MOVEit software.

No organization is immune to cyberattacks. That’s why it’s important for all organizations to take steps to protect their computer systems and data. This will result in safer, more dependable systems that everyone can trust.

Read on to see how you can ensure your organization is safe from cyberattacks.

The world of cybersecurity is extremely dynamic. With new threats evolving as quickly as the technology does, companies spend considerable amounts of money on cybersecurity each year. Understanding the history of cyberattacks can help to better comprehend the dangers of cybercrime as it exists today. 

As security measures become more advanced, so do cybercriminals’ methods of outmaneuvering them. This makes cybersecurity an essential issue that organizations must take seriously. Otherwise, they risk facing serious consequences. 

To mitigate the risk of cyberattacks and data breaches, companies need skilled cybersecurity teams capable of planning and executing robust strategies. This requires an investment in technology, advanced employee training, policy development, and continuous monitoring to stay ahead of evolving risks.

By committing to cybersecurity training, organizations can enhance their cybersecurity efforts, build robust defenses against cyber threats, and foster a culture of resilience.

Start protecting your company today and learn more about what cybersecurity training Skillsoft has to offer.