Blue Teaming

One-liner: Defensive security operations focused on detecting, preventing, and responding to cyber threats.

🎯 What Is It?

Blue teaming encompasses all defensive security activities—monitoring, detection, incident response, and hardening. Blue teams protect organizations by identifying and mitigating threats before, during, and after attacks.

🔵 Blue Team vs Red Team

🛡️ Core Blue Team Functions

1. Security Monitoring

• Log analysis via SIEM
• Network traffic analysis
• EDR monitoring

2. Threat Detection

• Detection Engineering — Building detection rules
• Indicator Detection — IOC matching
• Threat Behavior detections — TTP-based detection

3. Incident Response

• Alert triage and investigation
• Containment and eradication
• Recovery and lessons learned

4. Threat Intelligence

• Threat intel consumption
• IOC integration
• Threat landscape awareness

5. Security Hardening

• Vulnerability management
• Configuration hardening
• Patch management

🛠️ Essential Blue Team Tools

📊 Key Metrics

🎤 Interview STAR Example

Situation: SOC was overwhelmed with 500+ daily alerts, most were false positives.
Task: Reduce alert fatigue and improve detection quality.
Action: Analyzed 30 days of alerts, identified top noise sources, tuned 15 detection rules, created allowlists for known-good behavior.
Result: Reduced alerts by 60%, improved true positive rate from 15% to 45%.

🔗 Related Concepts

• Red Teaming
• Security Operations Center (SOC)
• Detection Engineering
• Pyramid of Pain
• MITRE ATT&CK

📚 References

• SANS Blue Team Operations
• MITRE D3FEND Framework