Detection Speed is Critical
The speed at which you detect ransomware directly correlates with damage:
- 1 minute: 0.1% of files encrypted (easily recoverable)
- 1 hour: 5-20% of files encrypted (significant impact)
- 24 hours: 80%+ of files encrypted (catastrophic)
Detection Timeline Targets
Ideal: Real-time (0-5 minutes)
- Automated alerts trigger
- Security team notified
- Incident response begins immediately
Acceptable: Within 15 minutes
- EDR detects suspicious activity
- Alerts reach security team
- Initial containment possible
Poor: 1-24 hours
- Manual discovery
- Significant encryption occurs
- Major damage unavoidable
Detection Methods
1. EDR Behavioral Analysis
- Monitors file system activity
- Detects mass encryption patterns
- Alerts on suspicious processes
- Real-time, 1-5 minute detection
2. Network Monitoring
- Detects unusual data flows
- Identifies C2 communications
- Monitors for exfiltration
- 5-15 minute detection
3. File Integrity Monitoring
- Watches critical directories
- Alerts on file modifications
- Detects encryption
- 5-10 minute detection
4. User Reports
- Staff notice locked files
- Unusual error messages
- System slowdowns
- 30 minute to hours detection
Implementing Fast Detection
Essential technologies:
- Endpoint Detection and Response (EDR)
- Security Information and Event Management (SIEM)
- Network intrusion detection (IDS)
- File integrity monitoring
- Backup integrity monitoring
Key configurations:
- Real-time alerting (not batched)
- Low thresholds triggering alerts
- Automated initial response
- Clear escalation procedures
- 24/7 monitoring
- After-hours on-call team
Measuring Detection Performance
Metric: Mean Time To Detection (MTTD)
- Target: <15 minutes
- Good: 15-60 minutes
- Acceptable: 1-4 hours
- Poor: >4 hours
Formula: (Detection time - Attack start time)
Rapid Response Requirements
Once detected:
- Immediate (0-5 min): Identify affected systems
- Within 5 min: Isolate from network
- Within 15 min: Begin containment
- Within 1 hour: Start recovery from backups
Every minute of delay means more encrypted files.
Conclusion
Organizations detecting ransomware within 15 minutes experience 70-80% less damage than those detecting after 1 hour. Investment in real-time detection capabilities pays dividends when attacks occur.
