Red Team, Blue Team, Purple Team: The Evolution of Adversarial Security Testing

Beyond Penetration Testing

The concept of adversarial security testing is older than the internet. The US military coined “red team” in Cold War wargaming exercises, where a dedicated group (red) would simulate Soviet tactics against US defenses (blue). The practice migrated to information security in the early 2000s, initially as an extension of penetration testing — authorized attempts to exploit vulnerabilities in systems. But while penetration testing focuses on finding and exploiting individual vulnerabilities within a defined scope and timeframe, red teaming simulates the full attack lifecycle of a real adversary: reconnaissance, initial access, persistence, lateral movement, privilege escalation, and objective completion.

The distinction matters enormously. A penetration test might find that a web application is vulnerable to SQL injection. A red team exercise discovers that a phishing email can bypass the email gateway, deliver a payload that evades endpoint detection, establish persistence via a scheduled task, move laterally using stolen credentials from a memory dump, escalate to domain administrator, and exfiltrate the organization’s most sensitive intellectual property — all while remaining undetected for the duration of the engagement. The red team tests not just technology but people, processes, and detection capabilities as an integrated system.

The global penetration testing and adversarial security testing market reached approximately $2.7 billion in 2025, driven by regulatory requirements (PCI DSS, the EU’s Digital Operational Resilience Act, and CBEST in the UK financial sector all mandate some form of adversarial testing), high-profile breaches that exposed detection failures, and the maturing understanding that you cannot know how good your defenses are until someone tests them with realistic attack techniques. Every major financial institution, critical infrastructure operator, and technology company now runs or contracts red team exercises. The question is no longer whether to test adversarially, but how to do it most effectively.

---

The Red Team Toolkit: Methodologies and Tools

Modern red team operations follow structured methodologies mapped to real adversary behavior. The MITRE ATT&CK framework — a globally accessible, empirically derived knowledge base of adversary tactics and techniques based on real-world observations — has become the de facto standard for organizing red team activities. ATT&CK catalogs 216 techniques and 475 sub-techniques across 14 tactical categories (Reconnaissance through Impact), each linked to documented use by specific threat groups. A red team planning an engagement against a financial institution might emulate the tactics of FIN7 or Carbanak, using ATT&CK mappings to ensure their simulated attack reflects the actual threat landscape.

The tools of the trade reflect this sophistication. Cobalt Strike, originally developed as a legitimate adversary simulation platform, remains the most widely used commercial red team tool despite its extensive abuse by actual threat actors (a fact that itself demonstrates its realism). Cobalt Strike’s “Beacon” payload supports encrypted command-and-control (C2) communications, in-memory execution, process injection, credential harvesting, and lateral movement — mirroring the capabilities of real malware frameworks. A Cobalt Strike license costs approximately $5,900 per operator per year. Alternatives include Brute Ratel C4, which emphasizes evasion of EDR (Endpoint Detection and Response) solutions, and open-source frameworks like Sliver (developed by BishopFox) and Mythic.

For automated adversary emulation, MITRE’s own Caldera platform allows teams to create automated attack plans using ATT&CK techniques, executing multi-step attack chains against target environments. Atomic Red Team, developed by Red Canary, provides a library of small, focused tests for individual ATT&CK techniques — useful for validating specific detection rules without running a full engagement. The combination of human-operated red team exercises (for testing complex attack chains and social engineering) and automated adversary emulation (for continuous validation of detection coverage) represents the current best practice for organizations with mature security programs.

---

The Purple Revolution: Collaborative Security Testing

The limitation of traditional red teaming is that it is adversarial by design — the red team’s success is measured by evading the blue team (the organization’s defenders). This creates a zero-sum dynamic where the red team has incentives to avoid areas where they know they will be detected, and the blue team learns about their failures only in a post-engagement debrief that may come weeks or months later. The defensive improvements are real but delayed, and the engagement’s value is concentrated in a final report rather than distributed throughout the process.

Purple teaming emerged as a response to this limitation. In a purple team exercise, offensive and defensive operators work collaboratively and iteratively. The red team executes a specific technique (for example, MITRE ATT&CK T1059.001 — PowerShell execution for command and scripting interpreter), the blue team observes their detection systems in real time, and both teams work together to understand: did the detection trigger? If not, why not? What log sources are missing? What detection rules need to be written or tuned? The process then repeats with the next technique. A purple team exercise might cover 50-100 ATT&CK techniques in a single week, producing immediate, actionable improvements to detection coverage.

The purple team approach has been adopted by organizations ranging from financial services firms complying with TIBER-EU (the threat intelligence-based ethical red teaming framework developed jointly by the European Central Bank and EU national central banks, now aligned with DORA compliance requirements) to technology companies running continuous purple team programs with dedicated staff. SpecterOps, the consultancy founded in 2017 by former NSA and defense intelligence operators including David McGuire (former NSA Red Team senior technical lead), has been instrumental in popularizing the methodology, alongside vendors like AttackIQ and SafeBreach that offer breach-and-attack simulation (BAS) platforms for automated purple teaming. The result is a shift from periodic, adversarial testing to continuous, collaborative validation — a more efficient model for organizations that want to improve defenses rather than simply prove they can be breached.

---

AI-Powered Red Teaming and the Career Landscape

The integration of AI into adversarial security testing is the field’s most significant current evolution. AI-powered red teaming tools can generate context-aware phishing emails that are significantly more convincing than template-based alternatives, automatically identify attack paths through complex Active Directory environments, and adapt their techniques in real time based on the defensive responses they encounter. Companies like Pentera (which introduced AI-driven capabilities in September 2025, now serving over 1,200 enterprises), XM Cyber (specializing in continuous exposure management and attack path simulation), and Horizon3.ai (whose NodeZero platform chains misconfigurations, unpatched vulnerabilities, and harvested credentials to map real attack paths) offer autonomous penetration testing platforms that can execute multi-step attack chains without human operators, running continuously against production environments.

The implications for human red teamers are nuanced. Automated tools excel at breadth — testing thousands of configurations, credentials, and attack paths at machine speed. But they lack the creativity, contextual judgment, and social engineering capability that make human red team operators effective against sophisticated defenses. The emerging model is hybrid: AI handles the initial reconnaissance and vulnerability scanning, identifies promising attack paths, and the human operator focuses on the creative exploitation, social engineering, and multi-vector attacks that automated tools cannot replicate. Rather than replacing red teamers, AI is eliminating the repetitive aspects of their work and amplifying their impact.

The career path from penetration tester to red team operator to red team lead is one of the most lucrative in cybersecurity. Senior red team operators at major consultancies (Mandiant, CrowdStrike, NCC Group) command base salaries of $130,000-$200,000 in US markets, with total compensation (including bonuses and equity) pushing higher — Mandiant’s senior red team consultants earn $132,000-$194,000 base with total packages reaching $180,000-$190,000+. Certifications like OSCP (Offensive Security Certified Professional), CRTO (Certified Red Team Operator), and GXPN (GIAC Exploit Researcher and Advanced Penetration Tester) are the standard credentials, but practical experience in CTF competitions, open-source tool development, and security research publications carry equal or greater weight. For Algerian cybersecurity professionals, the red team career path offers globally competitive compensation accessible through remote work — provided they invest in the skills, certifications, and demonstrable track record that international employers demand.

---

---

Sources & Further Reading

• MITRE ATT&CK Framework — Enterprise Techniques
• Cobalt Strike — Adversary Simulation and Red Team Operations
• BishopFox Sliver — Open Source Adversary Emulation Framework
• MITRE Caldera — Automated Adversary Emulation Platform
• Red Canary Atomic Red Team Library
• ECB TIBER-EU Framework
• Bank of England CBEST Threat Intelligence-Led Assessments
• SpecterOps — About
• Pentera — Automated Security Validation
• Horizon3.ai — Autonomous Penetration Testing
• Offensive Security OSCP Certification
• Penetration Testing Market Size and Growth — Fortune Business Insights