Red team, blue team, purple team: what's the difference

Security teams organize into offensive (red), defensive (blue), and collaborative (purple) roles. Here's what each does.

Red team

Red teamers simulate real attackers. The goal is to test whether defenses actually work against someone trying to break in - not just whether they exist on paper.

What they do:

Gain initial access (phishing, exploiting public-facing services, physical intrusion)
Establish persistence without getting caught
Move laterally through the network
Reach objectives: domain admin, sensitive data, critical systems

How it differs from pentesting: Pentests have defined scope and timeframes. Red team engagements are goal-oriented and may use any technique an attacker would - social engineering, physical access, custom malware. The blue team usually doesn't know it's happening.

Tools: C2 frameworks (Cobalt Strike, Sliver), custom implants, social engineering platforms.

Blue team

Blue teamers build and maintain defenses. They're the ones watching dashboards, writing detection rules, and responding when something goes wrong.

What they do:

Monitor security events through SIEM
Write and tune detection rules
Hunt for threats that evade automated detection
Respond to incidents
Manage vulnerabilities and patches

Tools:EDR solutions, network detection systems, SIEM platforms, threat intelligence feeds.

Purple team

Purple teaming puts red and blue in the same room. Instead of red team running an engagement and delivering a report weeks later, both sides work together in real time.

How it works:

Red team executes a specific technique (say, Kerberoasting)
Blue team tries to detect it
If detection fails, they figure out why and fix it immediately
Repeat for the next technique

Why it matters: Traditional red team engagements produce reports that sit in backlogs. Purple teaming creates immediate feedback loops. Defenders learn attacker techniques; attackers learn what gets detected.

When to use each

This depends on your maturity level:

Starting out: Focus on vulnerability assessments and basic pentesting
Intermediate: Add periodic red team engagements to test defenses
Mature: Implement purple team exercises for continuous improvement

If your blue team can't detect basic attacks, a full red team engagement will just produce a long list of failures without actionable improvements. Build detection capability first.

Mobile Application Penetration Testing: The Complete iOS and Android Security Guide
Mobile applications have become the primary interface between organizations and their users. Banking, healthcare,...
Cloud Penetration Testing: The Complete AWS, Azure, and GCP Security Assessment Guide
Cloud penetration testing: AWS, Azure, and GCPCloud security testing differs from traditional infrastructure...
OWASP Top 10 2026: The Complete Security Testing Guide for Modern Web Applications
The Open Web Application Security Project (OWASP) Top 10 represents the most critical security risks facing web...
Vulnerability Assessment vs Penetration Testing: The Complete Guide for 2026
In the ever-evolving landscape of cybersecurity, organizations face an increasingly complex challenge: how to...