What Is a Purple Team Exercise?
Purple team exercises combine red and blue team expertise to test detection coverage and close security gaps collaboratively.
What Purple Team Exercises Test
Purple team exercises select specific attack techniques from MITRE ATT&CK relevant to the organization's threat environment, execute them in the production or representative environment with the defensive team's knowledge, and evaluate whether each technique generates the expected alert, is visible in available telemetry but not alerted, or is completely invisible to existing controls.
The collaborative model produces three outcomes for each tested technique: the technique was detected as expected — no action needed; the technique generated telemetry but no alert — a detection rule can be written and the gap is closed; or the technique generated no telemetry — a logging gap that must be addressed before detection is possible. Each outcome drives specific improvement actions.
Purple Team vs. Red Team
Red team operations are adversarial and evaluative — red team operators work independently, attempting to achieve objectives without defender awareness, producing an assessment of whether the organization can detect and respond to realistic attacks. Purple team exercises are collaborative and developmental — attackers and defenders work together with shared information to identify and close specific detection gaps. Both have value; they serve different purposes. Red teams evaluate overall capability; purple teams improve specific detection coverage.
Running a Purple Team Program
Mature purple team programs operate on a continuous cadence rather than as one-time events. A quarterly purple team cycle selects the top ATT&CK techniques relevant to current threat intelligence, executes them collaboratively, measures detection performance, writes new detection content for gaps identified, and validates in the subsequent cycle that new content works as intended. This creates a systematic improvement loop that translates threat intelligence into specific, validated detection improvements.
Purple Team for PE Portfolio Companies
For PE-backed companies without mature internal security operations teams, purple team exercises are most effectively delivered through MDR providers who conduct collaborative validation of their own detection content. An MDR provider that operates purple team exercises against their own detection content — and can demonstrate measured detection coverage improvement over time — provides higher confidence in detection capability than one whose capability claims are based solely on tool certifications and analyst credentials.
Related Reading
What is a purple team exercise?
A purple team exercise is a collaborative security assessment that brings together offensive security specialists (red team) and defensive security operators (blue team) to test whether specific attack techniques are detected by existing security controls, identify detection gaps, and improve detection content in real time. Unlike red team operations where defenders are unaware of the attack, purple team exercises are transparent and collaborative — the goal is maximizing learning and improvement, not operational realism.
What's the difference between purple team and red team exercises?
Red team operations are adversarial and evaluative — red team operators work independently, attempting to achieve objectives without defender awareness, producing an assessment of whether the organization can detect and respond to realistic attacks. Purple team exercises are collaborative and developmental — attackers and defenders work together with shared information to identify and close specific detection gaps. Red teams evaluate overall capability; purple teams improve specific detection coverage. Mature programs use both: purple team continuously to improve detection, red team periodically to validate overall capability.
How does a purple team exercise work technically?
Purple team exercises select specific attack techniques from MITRE ATT&CK relevant to the organization's threat environment, execute them in the production or representative environment with the defensive team's knowledge, and evaluate three outcomes for each: the technique was detected as expected (no action needed); the technique generated telemetry but no alert (a detection rule can be written); or the technique generated no telemetry (a logging gap requiring infrastructure change). Each outcome drives specific improvement actions.
What tools support purple team exercises?
Atomic Red Team (open source) provides scripted tests for individual MITRE ATT&CK techniques that can be executed in production environments. Caldera (MITRE) provides automated adversary emulation for systematic testing. SafeBreach, AttackIQ, and Cymulate are commercial breach and attack simulation platforms that execute purple team tests at scale. The actual attack execution is straightforward; the value is in the collaboration between offensive operators selecting realistic techniques and defensive operators tuning detection content based on results.
How often should organizations run purple team exercises?
Mature programs run continuous purple team cycles — typically quarterly themed exercises that select the top ATT&CK techniques relevant to current threat intelligence, execute them collaboratively, measure detection performance, write new detection content for gaps, and validate in the subsequent cycle that new content works as intended. This creates a systematic improvement loop. Organizations starting purple team programs benefit from beginning with a small set of high-priority techniques and expanding scope as the team builds maturity and process.
How do PE portfolio companies access purple team capability?
For PE-backed companies without mature internal security operations teams, purple team exercises are most effectively delivered through MDR providers who conduct collaborative validation of their own detection content, or through specialized consulting engagements. An MDR provider that operates purple team exercises against their own detection content — and can demonstrate measured detection coverage improvement over time — provides higher confidence in detection capability than one whose claims are based solely on tool certifications and analyst credentials.
What is the most valuable first purple team exercise?
Test detection coverage for the techniques most commonly used in ransomware attacks against organizations of similar size and industry: credential theft (Mimikatz and equivalents), lateral movement through Active Directory (Kerberoasting, Pass-the-Hash), command-and-control beaconing (HTTPS C2 with jittered intervals), data staging and exfiltration, and ransomware execution. These techniques represent the highest-likelihood threat scenario, and validating detection coverage for them establishes a meaningful security posture baseline that translates directly to ransomware preparedness.
Real-World Example: Cloudskope Purple Team Reveals C2 Detection Gap
A purple team engagement for a PE-backed financial services company tested HTTPS-based C2 beaconing — specifically, Cobalt Strike Beacon traffic over port 443 with jittered intervals. The exercise revealed that while the organization's SIEM had correlation rules for known-bad C2 domains, it had no detection for behavioral beaconing patterns independent of domain reputation. The discovery enabled the security team to write and deploy behavioral detection rules that identified C2 activity through timing and volume patterns rather than domain blocklists — closing a gap that would have been exploitable by any attacker using infrastructure not already in threat intelligence feeds.
Of MITRE ATT&CK techniques go undetected in the average enterprise security environment — meaning most organizations have significant blind spots that purple team exercises are specifically designed to identify and close.