Team Exercise Modes
Red Teaming Red teaming simulates realistic adversary attacks to test detection and response capabilities. Red teams use stealthy, objective-based approaches with realistic TTPs. Red team objectives should be specific and measurable, such as exfiltrating specific data or gaining access to crown jewel systems. Objectives drive realistic attack paths. Red teams should use TTPs matching relevant threat actors. Realistic TTPs test real-world defenses. Red teams should operate stealthily to test detection capabilities. Noisy attacks do not test detection effectiveness. Red team duration should be sufficient for realistic attack progression (weeks to months). Short exercises miss slow-moving attacks. Blue Teaming Blue teaming focuses on defense operations including detection, response, and hardening. Blue teams defend against red team attacks and general threats. Blue team activities include monitoring, alert triage, incident response, threat hunting, and control hardening. Comprehensive defense requires multiple capabilities. Blue teams should operate as they would during real incidents. Exercises test real-world capabilities. Blue team effectiveness is measured by detection speed, response quality, and control improvements. Metrics drive improvement. Purple Teaming Purple teaming combines red and blue teams in collaborative, iterative improvement. Purple teams work together rather than adversarially. Purple teaming proceeds TTP-by-TTP, with red team demonstrating attack and blue team improving detection. Iteration drives systematic improvement. Purple teaming is more efficient than pure red teaming for detection development. Collaboration accelerates improvement. Purple teaming should cover MITRE ATT&CK tactics and techniques systematically. Systematic coverage ensures comprehensive improvement.Exercise Planning
Rules of Engagement Rules of engagement (RoE) define exercise scope, constraints, and safety measures. RoE prevent unintended damage. RoE should specify in-scope and out-of-scope systems, networks, and data. Scope prevents unintended impact. RoE should define prohibited actions including data destruction, service disruption, and physical access. Prohibitions prevent damage. Kill switches enable immediate exercise termination if issues arise. Kill switches are essential safety measure. Legal and privacy review should occur before exercises. Review prevents legal issues. Scoping Exercise scope should balance realism with safety. Overly constrained exercises lack realism; overly broad exercises risk damage. Production systems should be included where safe. Production testing provides realistic results. Crown jewel systems and data should be identified as objectives. Crown jewels drive realistic attack paths. Attack paths to crown jewels should be mapped. Path mapping guides red team and focuses blue team. Communications and Sponsorship Executive sponsorship ensures resources and organizational support. Sponsorship is critical for success. Communications plan should define who knows about exercise and when. Limited knowledge maintains realism. Deconfliction procedures prevent confusion with real incidents. Deconfliction is essential for production exercises. Post-exercise communications should share results and improvements. Communication demonstrates value. Threat Emulation Plans Threat emulation plans map exercises to MITRE ATT&CK tactics and techniques. Mapping ensures relevant testing. Emulation plans should be based on relevant threat actors and TTPs. Relevance ensures realistic testing. MITRE CTID (Center for Threat-Informed Defense) provides emulation plans for major threat actors. CTID plans accelerate planning. Emulation plans should include specific tools, techniques, and procedures. Specificity enables realistic emulation. Success Metrics Success metrics should be defined before exercise. Pre-agreed metrics prevent disputes. Detection metrics include percentage of TTPs detected, mean time to detect, and detection quality. Detection metrics measure defensive effectiveness. Response metrics include mean time to respond, containment effectiveness, and playbook execution. Response metrics measure operational effectiveness. Improvement metrics include new detections created, configurations hardened, and playbooks validated. Improvement metrics measure lasting value.Exercise Execution
Artifact Capture All red team commands, tools, and indicators should be captured. Artifacts enable blue team analysis and detection development. Artifacts should include command lines, file hashes, network indicators, and timestamps. Comprehensive artifacts enable detailed analysis. Artifacts should be shared with blue team after exercise. Sharing enables detection development. Operational Deconfliction Exercise activities should be deconflicted with normal operations. Deconfliction prevents confusion and unintended impact. Security operations center should be aware of exercise timing (for purple team) or have deconfliction contact (for red team). Awareness enables appropriate response. Exercise indicators should be tagged to prevent confusion with real threats. Tagging enables separation. Safety Checks Safety checks should occur throughout exercise. Checks prevent unintended damage. Data exfiltration should use test data or be simulated. Real data exfiltration creates risk. Service disruption should be avoided or carefully controlled. Disruption impacts business. Privilege escalation should be monitored to prevent unintended access. Monitoring prevents scope creep. Real-Time Adjustments Exercise scope and approach should be adjusted based on findings. Flexibility improves outcomes. If critical vulnerabilities are found, exercise may pause for remediation. Critical issues warrant immediate action. If blue team is overwhelmed, red team may slow pace. Overwhelming blue team reduces learning.Exercise Outcomes and Improvement
Detection Development New detections should be created for undetected TTPs. Detection development is primary outcome. Existing detections should be upgraded based on evasion techniques discovered. Upgrades improve detection quality. Detection coverage should be measured before and after exercise. Coverage improvement demonstrates value. Detections should be tested against red team artifacts. Testing validates detection effectiveness. Configuration Hardening Vulnerabilities and misconfigurations discovered should be remediated. Remediation reduces attack surface. Hardening should be prioritized by exploitability and impact. Prioritization focuses effort. Hardening should be validated through retesting. Validation ensures effectiveness. Playbook Validation Incident response playbooks should be executed during exercise. Execution validates playbooks. Playbook gaps and inefficiencies should be identified and addressed. Improvement makes playbooks more effective. Playbook updates should be documented and trained. Documentation ensures consistent execution. Retesting Improvements should be retested to validate effectiveness. Retesting ensures improvements work. Retesting should use same TTPs as original exercise. Consistency enables comparison. Retesting should show measurable improvement. Improvement demonstrates value. Metrics and Reporting Before and after metrics should be published. Metrics demonstrate improvement. Metrics should include detection coverage, MTTD, MTTR, and control effectiveness. Comprehensive metrics show full impact. Executive reporting should focus on risk reduction and improvements. Executive communication demonstrates value. Detailed technical reporting should document findings and remediations. Technical documentation enables learning.Purple Team Workflow
TTP Selection Select MITRE ATT&CK technique to test. Selection should prioritize high-risk techniques. Red Team Demonstration Red team demonstrates technique in environment. Demonstration should be realistic. Blue Team Detection Blue team attempts to detect technique. Detection attempt reveals gaps. Collaborative Improvement Red and blue teams collaborate to develop detection. Collaboration accelerates development. Detection Validation Red team validates detection by re-executing technique. Validation ensures detection works. Iteration Repeat for next technique. Iteration provides systematic coverage.Program Maturity
Ad Hoc Exercises Initial exercises are ad hoc and infrequent. Ad hoc exercises provide limited value. Regular Cadence Mature programs conduct exercises on regular cadence (quarterly or semi-annually). Regular cadence drives continuous improvement. Continuous Testing Advanced programs conduct continuous purple teaming. Continuous testing provides ongoing improvement. Breach and attack simulation (BAS) tools enable automated continuous testing. Automation scales testing.Conclusion
Red, blue, and purple teaming exercises test and improve security controls through adversary emulation and defense collaboration. Security engineers design exercises with clear objectives, realistic scope, and success criteria focused on lasting improvements. Success requires careful planning with rules of engagement and threat emulation plans, systematic execution with artifact capture and deconfliction, and conversion of findings into improved detections, hardened configurations, and validated playbooks. Organizations that invest in team exercise fundamentals continuously improve security controls.References
- MITRE ATT&CK Framework
- MITRE CTID (Center for Threat-Informed Defense) Emulation Plans
- NIST SP 800-115 Technical Guide to Information Security Testing
- Purple Team Exercise Frameworks
- Breach and Attack Simulation (BAS) Best Practices