Red Team, Blue Team, Purple Team: Understanding the Full Spectrum of Cybersecurity Defense

For years I worked as a red teamer, and getting that first shell on a target system defined my early career. For someone who conducted undercover operations as a federal agent, you would think the adrenaline would fade, but it did not. Over time, though, my perspective shifted. When I moved into defensive security operations, I discovered something equally demanding: the pressure of being right 100% of the time.

Red teamers need one successful attack to prove their point, while blue teamers must stop hundreds of attacks simultaneously without missing the one that matters. That fundamental difference reveals why modern cybersecurity cannot function with either team in isolation.

Every day, attackers develop new tactics and defenders must evolve to counter them. The organizations that thrive are those that break down the walls between offense and defense, creating feedback loops where each side makes the other stronger. That is where purple teaming enters as the real security transformation.

This blog walks through each team role, how they work together, and what it takes to build or join one.

What Is a Red Team?

A red team’s job is simple in theory, demanding in practice: simulate real-world attackers and find vulnerabilities before threat actors do.

Purpose: Simulating Real-World Attackers

Red teams go beyond vulnerability scanning. While a scanner flags outdated software, a red team asks: "How do I actually exploit this?"

Red teams conduct authorized penetration testing to identify and prove exploitability of weaknesses. They test human vulnerabilities through social engineering campaigns involving phishing and pretexting. They execute physical breach attempts to show how attackers gain access to restricted areas. Advanced multi-stage attacks demonstrate lateral movement and persistence mechanisms that prove an attacker can move through your environment and stay hidden. Cloud infrastructure exploits target common misconfigurations in AWS, Azure, or GCP.

Tools of the Trade

Red teams rely on a toolkit of tailor-made operating systems and exploit frameworks:

• Kali Linux: The comprehensive collection of offensive security tools, my constant companion through countless engagements
• Parrot OS: An equally capable alternative designed for pentesting, privacy research, and development
• Metasploit Framework: The industry standard for developing and delivering exploits
• Cobalt Strike: Advanced command and control for simulating sophisticated adversary behavior
• Custom tooling: Every mature red team builds proprietary tools tailored to their assessment approach

What Is a Blue Team?

While a red team needs one successful attack to prove exploitation, a blue team must defend against hundreds of attack vectors simultaneously, every single day.

Purpose: Detect, Defend, and Respond

Blue teams operate continuously to detect, investigate, and respond to threats. The work spans multiple domains: 24/7 security monitoring and log analysis to spot indicators of compromise, firewall management to prevent unauthorized movement, incident response to contain and remediate attacks, threat hunting to proactively search for signs of attacker activity, and defensive hardening through patching and configuration updates.

Transitioning from red to blue team taught me something unexpected: when you spot an attacker in your logs, when you see suspicious API calls that should not be there, when your Splunk search catches lateral movement in real-time, that is an adrenaline hit. You are not defending in the abstract. You are hunting. You are stopping attacks before they spread while the attackers are actually trying.

Tools and Platforms

Blue teams rely on different technologies, primarily focused on visibility and response:

• SIEM (Security Information and Event Management): Tools like Splunk aggregate and analyze logs from across the infrastructure. The skill is not just running searches; it is tuning queries to separate actionable signals from noise
• ELK Stack (Elasticsearch, Logstash, Kibana): A cost-effective alternative from Elastic for organizations collecting and visualizing log data
• Cribl: A platform that optimizes log collection and forwarding to reduce costs and improve signal quality
• EDR (Endpoint Detection and Response): Tools that monitor endpoints for suspicious behavior from vendors like CrowdStrike, Microsoft Defender, or Sentinel One
• IDS/IPS (Intrusion Detection/Prevention Systems): Network-based tools that detect and block suspicious traffic
• Threat Intelligence: Feeds from sources like Mitre ATT&CK, CrowdStrike, or Shodan that help contextualize alerts and prioritize response

What Is a Purple Team?

For years, red and blue teams operated in silos where red teams delivered reports that blue teams filed away. Purple teaming changes this dynamic by asking: "What if red and blue teams worked together to improve defenses?"

Purpose: Bridge the Gap Through Collaboration

A purple team can take different forms depending on organizational maturity. In some companies, it is a dedicated team that facilitates collaboration between red and blue. In others, it is a mindset and methodology where existing red and blue teams work together directly. Either way, purple teaming blends both perspectives:

• Shared objectives: Moving from "prove you can attack" to "help us defend better"
• Continuous feedback loops: Red team insights inform blue team detection; blue team gaps drive red team testing
• Knowledge sharing: Both sides learn from each other
• Iterative improvement: Test, defend, measure, refine, repeat

Collaboration Model

The purple team collaboration works through a specific dynamic. Red teams share detailed information about offensive methodologies, attack chains, and exploitation techniques. Blue teams take these tactical insights and use them to develop enhanced detection rules and response procedures. Purple teaming validates that these defenses work against actual attacks, identifies remaining gaps, and drives continuous improvement.

Outcome: Accelerated Security Improvement

The result of effective purple teaming is accelerated security improvement through knowledge sharing. Organizations do not just find vulnerabilities and fix them in isolation; they build a culture where offensive and defensive perspectives continuously inform each other.

I have worked as an overt pentester in organizations where purple teaming was built into engagements. The difference is profound. Instead of delivering a report and leaving, you are in the room with the SOC team, showing them how their detection tools can catch your attacks, tuning Splunk queries together, and collaborating on response playbooks.

How Red, Blue, and Purple Teams Work Together

In immature security operations, these teams do not work together; they often work against each other. Red teams feel blue teams are missing obvious attacks. Blue teams feel red teams are unrealistic. Purple teaming breaks this cycle by establishing shared goals.

Breaking Down Silos

When red and blue teams collaborate:

• Red teams gain context: Understanding how blue teams detect attacks helps red teams assess real risk, not just theoretical vulnerabilities
• Blue teams gain insight: Seeing attacks firsthand reveals blind spots in monitoring and response
• Organizations gain efficiency: Both teams work together to close gaps immediately
• Threat intelligence improves: Red team findings inform blue team hunting priorities

Real-World Purple Team Engagement

Consider an AWS attack chain where an attacker gains EC2 access through a misconfigured application. A purple team would:

1. Red team executes: Gain initial EC2 shell access through a web application CVE, retrieve AWS credentials via the Instance Metadata Service (IMDS) using Metasploit, and demonstrate lateral movement
   
2. Blue team monitors: The SOC monitors EC2 logs, firewall traffic, and CloudTrail through Splunk, looking for suspicious API calls and indicators of compromise
   
3. Both teams debrief: The red team shows what artifacts were left behind. The blue team discusses what was detected and what gaps exist, discovering perhaps that IMDS requests were not logged
   
4. Refinement: The blue team enables CloudTrail logging and writes Splunk searches to detect anomalous API calls. The red team adjusts tactics
   
5. Validation: Re-execute to confirm detection rules work
   

By the end, the organization has proven its detection capabilities and documented the playbook for future incidents.

When Does an Organization Need Each Team?

Organizations do not mature all at once, and neither do their security programs. The teams you need depend on where you are in your company lifecycle.

Startup Phase: Early-stage companies operate with limited budgets and cannot justify internal red teams. They rely on external penetration testers for annual assessments and implement basic log monitoring. Blue team work is minimal and compliance-driven.

Growth Phase: As organizations expand, they hire dedicated security personnel who wear both offense and defense hats. They conduct annual external pentests while building internal assessment capabilities. SIEM platforms like Splunk get deployed. Purple teaming begins informally, maybe the external pentester sticks around for a week to help the team understand how findings translate to detection.

Enterprise Maturity: Large organizations maintain dedicated red and blue teams with distinct responsibilities. Red teams operate continuously with multiple assessment types throughout the year. SOCs achieve full maturity with integrated SIEM platforms, enterprise-wide EDR deployment, and automated response mechanisms. These organizations run formal purple team programs where red and blue teams collaborate on scheduled scenarios, and some may even establish dedicated purple teams for ongoing collaboration and validation. The security organization develops specialized roles including threat hunters who proactively search for adversaries, incident responders with deep forensics expertise, and security architects who design comprehensive security strategies.

Build vs. Buy: Red teaming is often outsourced to gain external perspective and fresh attack methodologies. Blue teaming is typically built in-house because it requires intimate knowledge of your specific infrastructure, applications, and business processes. Purple teaming usually follows a hybrid model where internal blue teams work with external red teamers, or internal red teams collaborate with the SOC on controlled scenarios. Some mature organizations build dedicated purple teams to facilitate ongoing collaboration and continuously validate security controls.

Career Paths: Which Team Is Right for You?

Understanding these team structures is critical if you are building a cybersecurity career. The path you choose impacts the skills you develop, the certifications that matter to employers, and the mindset you cultivate.

Red Team Career Path

Red teamers are problem-solvers. They need technical skills (scripting, networking, system administration), creative thinking, persistence, and operational security mindset.

Key Certifications:

• OSCP (Offensive Security Certified Professional): The gold standard from Offensive Security with a 48-hour practical exam where you must exploit real vulnerabilities
• CEH (Certified Ethical Hacker): EC-Council certification well-recognized in government and DoD environments
• GPEN (GIAC Penetration Tester): From GIAC, validates hands-on penetration testing with practical exam components

Mindset: Red teamers live for that moment when code execution is achieved. The work is intellectually demanding, and success comes through methodical persistence.

Blue Team Career Path

Blue teamers are analysts and strategists. They need analytical skills, tool proficiency (SIEM, EDR, firewalls), strong communication, and patience with false positives.

Key Certifications:

• CompTIA CySA+ (Cybersecurity Analyst+): The premier blue team credential from CompTIA validating data analysis and threat identification with performance-based questions
• CompTIA Security+: Foundational credential from CompTIA covering network security, cryptography, and compliance
• GIAC GCIA (Intrusion Analyst): From GIAC, specializes in network intrusion detection with hands-on packet capture
• Splunk Certifications: Validate hands-on SIEM deployment and optimization

Mindset: Where red teamers thrive on finding the one thing that breaks the system, blue teamers take pride in stopping true positives from thousands of alerts daily. The victory is not flashy, but it is continuous and aligned with keeping organizations safe.

Purple Team / Hybrid Path

Purple teamers are translators and system thinkers. They need red team fundamentals to understand real attacks, blue team fundamentals to recognize detection gaps, communication mastery, and strategic thinking.

Key Certifications:

• Both paths: OSCP plus CySA+ demonstrates mastery across the spectrum
• SANS SEC599: Defeating Advanced Adversaries teaches purple team methodology
• Specialized certifications in threat intelligence (GCTI) and incident response (GCIH) from GIAC

Mindset: The best purple teamers have spent time on both sides. They understand red team creativity without losing blue team discipline. They appreciate that the goal is not to "win" an engagement; it is to improve security outcomes.

Conclusion

Red teams find the problems, blue teams solve them, and purple teams ensure the two work together effectively.

Organizations that maintain red teams without corresponding blue team capability create reports that nobody acts on, while organizations that build blue teams without red team input end up defending against yesterday attacks. The organizations that thrive embrace the full spectrum: proactive offense, continuous defense, and collaborative iteration.

Purple teaming is no longer a luxury. As threats become more sophisticated, the feedback loop between red and blue teams is critical to modern threat detection and prevention. Organizations that integrate offensive insights directly into their defensive operations do not just catch more attacks; they understand the attackers’ mindset and can anticipate future tactics.

If you are starting your cybersecurity career, do not think of red versus blue as a binary choice. The most valuable security professionals understand both perspectives. For those pursuing the blue team path, the CompTIA CySA+ credential is your validation, and the Cybrary CySA+ certification path provides structured training with hands-on labs. For those wanting to "hack the planet," the penetration tester career path from Cybrary covers certifications like CEH and OSCP.

The security teams winning today do not work in silos. They collaborate, they adapt, and they iterate. Be part of that team. Start your red, blue, or purple team career path today with Cybrary!