The Most Common Methods Behind Major Data Breaches

The Most Common Methods Behind Major Data Breaches
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Data breaches have evolved in sophistication, but many attackers still rely on proven tactics to exploit vulnerabilities. Based on analysis of breaches from 2020–2025, here are the most prevalent methods used globally, along with real-world examples and statistics.

The 15 Most Devastating Data Breaches in History
From nation-state cyberattacks to corporate security failures, these breaches exposed billions of records and reshaped global cybersecurity practices. Navigating the Cyberstorm: A Deep Dive into Global Data BreachesIntroduction In today’s interconnected world, cybersecurity incidents are not a matter of if, but when. A recent data breach highlights the ever-present

1. Credential-Based Attacks (37% of breaches)

Methods:

  • Phishing: Fraudulent emails or messages trick users into revealing passwords.
  • Brute Force: Automated tools guess weak passwords (e.g., "123456").
  • Credential Stuffing: Reusing stolen credentials across platforms.

Statistics:

  • 37% of breaches in 2024 involved credential theft (Verizon DBIR 2024).
  • Stolen credentials cost companies $4.62M per breach on average (IBM, 2023).

Examples:

  • 23andMe (2023): Hackers used credential stuffing to access 6.9 million accounts via reused passwords.
  • Colonial Pipeline (2021): Attackers breached an employee’s VPN using a password found on the dark web.

2. Social Engineering (40% of breaches)

Tactics:

  • Business Email Compromise (BEC): Impersonating executives to trick employees into wiring funds.
  • Phishing: 16% of breaches start with phishing (IBM, 2024).

Impact:

  • $4.76M: Average cost of phishing-related breaches (IBM).
  • LinkedIn (2021): Hackers posed as recruiters to steal corporate credentials.

3. Exploiting Vulnerabilities (24% of breaches)

Common Weaknesses:

  • Unpatched Software: Equifax’s 2017 breach stemmed from an unpatched Apache Struts flaw.
  • SQL Injection: Injecting malicious code into databases (e.g., Heartland Payments, 2008).

Trends:

  • Zero-Day Exploits: Accounted for $4.45M per breach in 2023 (IBM).
  • MOVEit (2023): Russian hackers exploited a file-transfer tool to steal 60+ million records.

4. Ransomware (24% of Malware Breaches)

Process: Encrypt data and demand payment for decryption.
Costs:

  • $4.91M: Average ransomware breach cost (IBM).
  • Colonial Pipeline: Paid $4.4M in Bitcoin after a DarkSide ransomware attack halted fuel distribution.

Targets: Healthcare, education, and critical infrastructure.


5. Insider Threats (65% of breaches)

Types:

  • Malicious Insiders: Employees selling data (e.g., Tesla staff leaking customer info in 2023).
  • Negligence: Accidental exposure of sensitive files (e.g., misconfigured cloud storage).

Stats:

  • Insider breaches take 85 days to contain (IBM).
  • Meta (2024): Contractors improperly shared user data with third parties.
Real-World Examples of LGPD Fines and Enforcement Actions in Brazil
Brazil’s Lei Geral de Proteção de Dados (LGPD) has seen increased enforcement since its penalties took effect in August 2021. Below are key cases and fines imposed by the Brazilian National Data Protection Authority (ANPD), illustrating how the law is applied across sectors and organization sizes. The Brazilian General

6. Physical Theft/Loss

Examples:

  • Lost laptops or USB drives containing unencrypted data.
  • Samsung (2022): A stolen device exposed proprietary chip designs.

Mitigation: Encryption reduces risk by 50% (Kaspersky).


7. Supply Chain & Third-Party Vulnerabilities

Attacks:

  • SolarWinds (2020): Russian hackers compromised software updates to breach 18,000 organizations.
  • Target (2013): HVAC vendor access led to 40M credit cards stolen.

Trend: 62% of breaches in 2024 involved third parties (Ponemon Institute).


8. Malware & Spyware

Common Tools:

  • Keyloggers: Record keystrokes to steal passwords (e.g., Sony PlayStation breach, 2011).
  • Spyware: Monitors user activity covertly.

Case: Marriott (2018): Chinese state actors used malware to steal 500M guest records over four years.


9. Cloud Misconfiguration

Impact:

  • 80% of cloud breaches result from misconfigured storage buckets (Gartner, 2024).
  • Exactis (2018): 340M records exposed via an unsecured Elasticsearch server.

10. Denial-of-Service (DoS) Attacks

Purpose: Disrupt services to distract from concurrent breaches.

  • AWS (2020): A 2.3 Tbps DDoS attack masked a data exfiltration attempt.
Ten Major GDPR Fines: Lessons in Accountability, Transparency, and Compliance
As the General Data Protection Regulation (GDPR) matures, enforcement actions continue to underscore the regulation’s wide-ranging impact. The five cases below—spanning AI-driven chatbots to streaming services and real estate—demonstrate how regulators are intensifying scrutiny on key requirements such as timely breach reporting, valid legal bases for data

  1. Rise of AI-Driven Attacks: Phishing emails generated via ChatGPT increased by 135% in 2024.
  2. Global Regulation: GDPR fines hit €4B+ since 2018, pushing adoption of CCPA, LGPD, and DPDPA.
  3. Critical Infrastructure Focus: 45% of ransomware targets energy/healthcare sectors.
Global Data Protection Enforcement Beyond GDPR: Key Frameworks and Trends
The European Union’s General Data Protection Regulation (GDPR) has long been the gold standard for data privacy, but a wave of new regulations worldwide is reshaping the global compliance landscape. From California to Vietnam, governments are imposing stricter rules and heavier penalties to protect personal data, reflecting heightened public

Prevention Strategies

  • Zero Trust: Verify every access request.
  • Multi-Factor Authentication (MFA): Blocks 99% of credential attacks (Microsoft).
  • Employee Training: Reduces phishing success rates by 50% (KnowBe4).

As cybercriminals innovate, organizations must prioritize proactive defense to avoid becoming the next headline.


Sources: Verizon DBIR 2024, IBM Cost of a Data Breach 2023, Kaspersky, Gartner.

Citations:
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