Cybercrime Examples (2024): The 10 Worst Attacks of All Time

By Tibor Moes / Updated: May 2024

Cybercrime Examples (2023): The 10 Worst Attacks of All Time

Cybercrime represents a significant and growing threat in our digitally interconnected world, impacting individuals, businesses, and governments alike with devastating consequences.

This article delves into the ten most catastrophic cyber-attacks in history, offering insightful statistics and analyses to understand their scale and impact.


Cybercrime refers to criminal activities carried out using computers and the internet, often targeting digital data and systems.

  • ILOVEYOU Virus (2000): A computer worm that rapidly spread through email attachments. It infected over ten million Windows PCs, causing widespread system failures.
  • Code Red Worm (2001): This worm exploited web server vulnerabilities, infecting over 359,000 systems in less than 14 hours and causing damages exceeding $2 billion.
  • MyDoom Worm (2004): Regarded as one of the worst viruses ever, MyDoom caused $38 billion in damages and infected around 50 million computers globally.
  • Zeus Trojan Horse (2007): A Trojan that compromised over 74,000 FTP accounts, including those of major companies, allowing extensive data theft.
  • Conficker Worm (2008): This worm infected between 9 million to 15 million computers, exploiting Windows vulnerabilities to propagate itself.
  • Stuxnet Worm (2010): A sophisticated cyber weapon that ruined nearly one-fifth of Iran’s nuclear centrifuges and infected over 200,000 computers.
  • Home Depot Data Breach (2014): A massive breach in retail security, resulting in the theft of 56 million customer credit and debit card numbers.
  • WannaCry Ransomware Attack (2017): A global ransomware campaign that infected around 200,000 computers across 150 countries, with financial losses potentially reaching $4 billion.
  • NotPetya Attack (2017): Initially targeting Ukraine, this attack spiraled globally, causing over $10 billion in damages.
  • Equifax Data Breach (2017): A massive data breach that exposed the personal information of approximately 147 million people, highlighting significant vulnerabilities in data protection.

Don’t become a victim of cybercrime. Protect your devices with the best antivirus software and your privacy with the best VPN service.

Cybercrime Examples

1. ILOVEYOU Virus (2000)

In the early days of the new millennium, a digital menace known as the ILOVEYOU virus emerged, wreaking havoc on a scale previously unseen in the realm of cybercrime. Originating on May 5, 2000, this cunning computer worm infiltrated over ten million Windows PCs worldwide.

The virus, deceptively simple in its execution, spread rapidly through email, luring unsuspecting users with the promise of an affectionate message.

As reported by Wired, this virus was not just a fleeting annoyance but a significant disruptor, causing widespread system failures and data loss, marking a new era in the vulnerability of personal computing.

2. Code Red Worm (2001)

Just a year after the ILOVEYOU incident, the digital world encountered another formidable adversary: the Code Red worm. This malicious code, discovered in July 2001, demonstrated an alarming efficiency by infecting more than 359,000 systems in under 14 hours.

As detailed in a case study on ResearchGate, the impact of Code Red was far-reaching and costly. With a staggering damage estimate of over $2 billion, the worm highlighted the escalating economic repercussions of cyber-attacks.

It exploited vulnerabilities in web servers, transforming them into agents of chaos that multiplied and spread across the internet at an astonishing pace.

3. MyDoom Worm (2004)

In 2004, the cyber world was shaken by the emergence of the MyDoom worm, a threat that rapidly claimed its place as one of the most destructive viruses of its time.

NordVPN reports that MyDoom inflicted an astonishing $38 billion in damages, a figure that underscores the immense economic impact of this digital plague. The worm’s reach was vast and indiscriminate, infecting around 50 million computers globally.

Its method of propagation, primarily through email, capitalized on human curiosity and negligence, allowing it to spread at a phenomenal rate. MyDoom wasn’t just a technological threat; it was a stark reminder of the fragility of digital infrastructure in the face of well-crafted malicious software.

4. Zeus Trojan Horse (2007)

The Zeus Trojan Horse, first identified in 2007, marked a new chapter in cybercrime, one characterized by sophisticated attacks on financial and personal data.

A 2009 discovery, as reported in an archived article from The Tech Herald, revealed that Zeus had compromised over 74,000 FTP accounts across numerous high-profile websites, including those of Bank of America, NASA, and Amazon. This Trojan Horse didn’t just breach systems; it infiltrated them with a precision that allowed cybercriminals to siphon off a treasure trove of sensitive information.

The revelation of such extensive infiltration into the websites of major corporations like Oracle and Cisco highlighted not just the technical prowess of the attackers but also the alarming vulnerabilities in systems we trust with our most sensitive data.

5. Conficker Worm (2008)

In 2008, the digital world grappled with the Conficker worm, a formidable cyber threat that exemplified the escalating sophistication of malware.

According to Wikipedia, by January 2009, Conficker had entrenched itself in a staggering number of systems, with estimates ranging from 9 million to 15 million infected computers. This worm was not just prolific in its spread; it was also insidiously versatile, exploiting vulnerabilities in Windows operating systems and then using networks to propagate itself further.

The sheer scale of the infection highlighted the critical need for robust cybersecurity measures, as Conficker’s ability to disable security services and evade detection made it a formidable adversary in the evolving landscape of digital threats.

6. Stuxnet Worm (2010)

Two years after Conficker, the cyber landscape witnessed the emergence of Stuxnet, a worm of unprecedented sophistication and precision.

As detailed in an archived report from MAC Solutions, Stuxnet’s impact was specific yet catastrophic: it ruined nearly one-fifth of Iran’s nuclear centrifuges by targeting industrial control systems. The worm infected over 200,000 computers, but its most chilling effect was the physical degradation it caused to 1,000 machines.

Stuxnet represented a new frontier in cyber warfare, where digital tools were used to cause tangible, real-world damage. This cyber attack wasn’t just about stealing data or causing disruptions; it was about wielding digital prowess to exert control over critical physical infrastructures.

7. Home Depot Data Breach (2014)

The Home Depot data breach of 2014 stands as a stark reminder of the vulnerabilities inherent in retail cybersecurity. In a comprehensive report by Krebs on Security, it was revealed that an estimated 56 million debit and credit card numbers were stolen from Home Depot customers over a span of five months, from April to September 2014.

This breach wasn’t just a staggering violation of customer trust; it underscored the growing sophistication of cybercriminals in targeting point-of-sale systems. As one of the largest data breaches in retail history, the Home Depot incident highlighted the critical need for enhanced security protocols and raised serious concerns about consumer data safety in an increasingly digital shopping landscape.

8. WannaCry Ransomware Attack (2017)

2017 witnessed one of the most widespread and devastating cyberattacks in history: the WannaCry ransomware campaign. Europol described the scale of this attack as unprecedented, with around 200,000 computers infected across 150 countries, as reported by BBC News and CBS News.

The financial and economic fallout from WannaCry was colossal, with estimates suggesting losses could reach up to $4 billion. This cyber onslaught did not just lock out users and demand ransom; it paralyzed essential services, including hospitals, banks, and transportation systems.

The global reach and severe impact of WannaCry served as a wake-up call about the destructive potential of digital threats in a highly interconnected world.

9. NotPetya (2017)

In the annals of cyber warfare, NotPetya stands out for its sheer destructiveness. It was not just another malware; it was akin to a digital wildfire, uncontainable and indiscriminate.

In 2017, painted a grim picture of the aftermath, reporting that NotPetya caused an astronomical $10 billion in global damages. This staggering figure underscores the cataclysmic impact NotPetya had on businesses and governments worldwide. It didn’t just cross borders; it tore them down, leaving a trail of financial ruin that reverberated through the global economy.

NotPetya was more than a wake-up call; it was a sledgehammer to the illusion of digital security, proving that in the cyber realm, the potential for chaos is always just a click away.

10. Equifax Breach (2017)

Fast forward to 2017, and we encounter the infamous Equifax breach. Equifax, one of the major credit reporting agencies, experienced a massive breach that laid bare the personal data of approximately 147 million people. To understand the scale of this, picture nearly half the population of the United States having their sensitive data like social security numbers, birth dates, and addresses, exposed to unknown entities.

This breach was a startling reminder of the vulnerability of personal financial information and the catastrophic consequences of failing to protect it. The Equifax incident highlighted the need for robust security measures in protecting sensitive consumer data and the far-reaching impacts such security lapses can have on individuals and the economy.


The ten cyberattacks we’ve explored in this article, ranging from the ILOVEYOU virus to the Equifax data breach, illustrate the ever-evolving and increasingly sophisticated nature of cyber threats. These incidents have not only resulted in significant economic losses but also highlighted the vulnerability of personal, corporate, and governmental data. The scale and impact of these attacks underscore the crucial need for vigilance and proactive measures in the digital realm.

In response to these growing cyber threats, particularly for users of Windows 11, the importance of robust antivirus software cannot be overstated. Investing in reliable antivirus solutions from reputable brands like Norton, Avast, TotalAV, Bitdefender, McAfee, Panda, or Avira is more than just a safety measure; it’s an essential component of digital hygiene.

These tools provide crucial defense mechanisms against malware, ransomware, and other cyber threats, ensuring that your data remains secure and your digital experience uninterrupted. In a world where cybercrime is a persistent and ever-changing challenge, equipping your system with effective antivirus software is a key step in safeguarding your digital life.


Author: Tibor Moes

Author: Tibor Moes

Founder & Chief Editor at SoftwareLab

Tibor has tested 39 antivirus programs and 30 VPN services, and holds a Cybersecurity Graduate Certificate from Stanford University.

He uses Norton to protect his devices, CyberGhost for his privacy, and Dashlane for his passwords.

You can find him on LinkedIn or contact him here.