The 20 most notorious cyberattacks in history

Today we’re bringing a slightly different article. We usually focus on cyberattack prevention or more technical cybersecurity topics. However, this time we’re reviewing some of the most notorious cyberattacks in history—incidents that posed serious risks to the companies affected. We’ll also share practical cybersecurity recommendations so you can better protect your organization and avoid becoming part of this list.

The 20 most dangerous cyberattacks to date

PlayStation Network

77 million accounts were offline for nearly a month. In 2011, PlayStation was hacked due to a security breach that exposed data (names, emails, passwords, addresses, etc.) from nearly 80 million users. The attack was so severe that PlayStation Network remained down for weeks, causing losses of around €100 million.

Sony Pictures

Sony lost over $200 million after a cyberattack in 2014. The breach exposed a large portion of its internal database, including confidential documents such as executive salaries, employee personal data, and even unreleased films.

After a long investigation, the FBI attributed the attack to North Korea.

Yahoo

Yahoo lost $50 million in compensation to affected users. In 2013, it suffered a major data breach involving passwords and personal and banking information. The situation worsened in 2014 with another similar attack affecting 500 million accounts.

Telefónica

In 2017, Telefónica—along with other companies like Everis—was hit by the WannaCry ransomware attack. This global attack caused €3.5 billion in losses, infecting 300,000 computers across 150 countries. WannaCry encrypted sensitive data and demanded ransom payments for its recovery.

Tesco Bank 

In 2016, cybercriminals stole over £2.26 million from the bank in just 48 hours. Around 40,000 accounts showed suspicious transactions. In addition to the financial loss, Tesco Bank was fined £16.4 million due to insufficient cybersecurity measures.

Celebgate

In 2014, a cybercriminal used social engineering to obtain and leak private content from Hollywood actresses. Victims included Jennifer Lawrence, Kate Upton, and Kirsten Dunst.

Ashley Madison

A cyberattack cost the dating platform over $30 million. Personal data from more than 37 million users was exposed.

Adobe

In 2013, Adobe suffered a breach that compromised records and credit card data from over 150 million users. Initially reported as 3 million, the scale turned out to be far larger.

Canva

In 2019, a cyberattack compromised data from more than 61 million Canva accounts.

Facebook

In 2018, Facebook admitted storing millions of Instagram passwords in plain text. In 2019, another breach exposed 400 million phone numbers linked to accounts, along with names, locations, and gender data.

Twitter

In 2018, Twitter accidentally stored passwords in an internal log, exposing 330 million credentials within its internal network for months. Users were asked to reset their passwords as a precaution.

Marriot Internacional

In 2018, Marriott revealed that hackers had stolen data from approximately 500 million customers. The breach actually began in 2014. Stolen data included names, contact details, travel information, and passport numbers.

Stuxnet

In 2010, the Stuxnet virus infiltrated systems, stole information, and later instructed them to self-destruct.

Analysts and experts state that Stuxnet delayed Iran’s nuclear program, causing significant physical damage. The official impact data was never disclosed by the Iranian government.

Equifax

In 2017, Equifax exposed personal data from 143 million users, including Social Security numbers, credit cards, and addresses.

Ebay

In May 2014, eBay asked its 145 million users to reset their passwords after detecting a cyberattack on its network.

Uber 

In 2016, data from 57 million users and 7 million drivers was exposed. Uber paid $100,000 to hackers to delete the data and keep the breach secret.

Dropbox

The attack took place in 2012, but its full scale wasn’t revealed until four years later.

In 2012, Dropbox confirmed that its users’ email addresses had been exposed and their passwords stolen. In total, more than 68 million users were affected.

Epsilon (2011)

A series of attacks targeting email data cost around $3 billion.

NASDAQ

Between 2005 and 2012, attackers accessed data from 160 million users, exposing corporate secrets and private communications of executives, impacting the stock market.

Google China (2009)

Known as Operation Aurora, this series of attacks targeted Google and over 30 other companies, aiming to access activist accounts. Google reported limited success from the attackers.

The breach exploited Internet Explorer vulnerabilities, prompting governments like Germany, France, and Australia to recommend alternative browsers.

ESED recommendations to prevent cyberattacks

Implementing cybersecurity solutions, defining a clear strategy, and training employees are essential to prevent security breaches.

At ESED, we work with solutions such as:

• Anti-phishing solutions: We control email flow to ensure only verified messages reach users, blocking unauthorized delivery attempts.

• Endpoints: Endpoint XDR helps trace the origin of a threat, isolating compromised devices to prevent its spread and automatically removing it.

• Firewalls: AI-based firewalls enable exploit prevention and identify threats before they access your network, with automated accuracy thanks to security synchronized with other security products such as endpoints.

• Phishing simulators: We send previously selected and configured malicious emails to members of an organization to assess their security level.

• Backup solutions: We work with the 3-2-1 backup rule: keep at least 3 copies of your data, store copies on 2 different types of media, and keep 1 offsite backup copy.

• Credential managers: We offer an internal credential storage service, both cloud-based and on-premise, for your company’s infrastructure and users.

The implementation of these security measures provides the protection a system needs to prevent security breaches that can lead to malware entering a system.