// Cybersecurity

Ransomware

Ransomware is a type of malicious software that encrypts an organization's data or systems and demands payment (a ransom) for the decryption key. Modern ransomware attacks often include data theft and threats to publish stolen data (double extortion).

cybersecuritymalwareextortionincident responsedata breach

Why It Matters

Ransomware has become a multibillion-dollar criminal industry. Attacks don't just lock your files — modern ransomware gangs steal data first, then encrypt systems, threatening to publish the stolen data unless a ransom is paid. This "double extortion" means even organizations with good backups face significant risk. Under GDPR, a ransomware attack involving personal data is a reportable data breach.

How Ransomware Works

  1. Initial access — typically through phishing emails, compromised credentials, or exploiting unpatched vulnerabilities
  2. Lateral movement — attackers move through the network, escalating privileges and identifying valuable data
  3. Data exfiltration — sensitive data is stolen before encryption (for double extortion leverage)
  4. Encryption — files and systems are encrypted, rendering them unusable
  5. Ransom demand — a note demands payment (usually in cryptocurrency) for decryption keys and a promise not to publish stolen data

Compliance Implications

  • GDPR Article 33 — ransomware involving personal data triggers the 72-hour breach notification obligation
  • NIS2 — essential and important entities must report significant incidents within 24 hours (early warning) and 72 hours (full notification)
  • CIRCIA — US critical infrastructure entities must report within 72 hours, and ransom payments within 24 hours
  • HIPAA — healthcare ransomware incidents involving ePHI are presumed reportable breaches

Response Steps

  1. Isolate affected systems immediately to prevent spread
  2. Do not pay the ransom — there's no guarantee of data recovery, and payment funds further attacks
  3. Preserve evidence for law enforcement and forensic analysis
  4. Activate incident response plan and notify relevant stakeholders
  5. Report to authorities — supervisory authority (GDPR), CERT/CSIRT (NIS2), law enforcement
  6. Restore from backups if available and verified clean
  7. Communicate with affected individuals if personal data is at risk

Prevention

  • Regular patching of operating systems and software
  • Offline backups tested regularly (3-2-1 rule: 3 copies, 2 media types, 1 offsite)
  • Network segmentation to limit lateral movement
  • MFA on all remote access and privileged accounts
  • Employee training on phishing recognition
  • Endpoint detection and response (EDR) tools

Key Statistics

  • Average ransomware recovery cost: $1.82 million (Sophos, 2023)
  • Average downtime after attack: 24 days
  • 75% of ransomware attacks begin with a phishing email
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