A red team exercise is a simulated cyber attack conducted by a group of ethical hackers or security experts (the red team) against an organization’s network, systems, and staff (the blue team) to test the organization’s ability to detect, respond, and recover from a real cyber attack. A red team exercise provides an information security manager with the most accurate indication of the organization’s ability to respond to a cyber attack, because it mimics the tactics, techniques, and procedures of real threat actors, and challenges the organization’s security posture, incident response plan, and security awareness in a realistic and adversarial scenario12. A red team exercise can measure the following aspects of the organization’s cyber attack response capability3:

The effectiveness and efficiency of the security controls and processes in preventing, detecting, and mitigating cyber attacks

The readiness and performance of the incident response team and other stakeholders in following the incident response plan and procedures

The communication and coordination among the internal and external parties involved in the incident response process

The resilience and recovery of the critical assets and functions affected by the cyber attack

The lessons learned and improvement opportunities identified from the cyber attack simulation

The other options, such as a walk-through of the incident response plan, a black box penetration test, or a simulated phishing exercise, are not as accurate as a red team exercise in indicating the organization’s ability to respond to a cyber attack, because they have the following limitations4 :

A walk-through of the incident response plan is a theoretical and hypothetical exercise that involves reviewing and discussing the incident response plan and procedures with the relevant stakeholders, without actually testing them in a live environment. A walk-through can help to familiarize the participants with the incident response roles and responsibilities, and to identify any gaps or inconsistencies in the plan, but it cannot measure the actual performance and effectiveness of the incident response process under a real cyber attack scenario.

A black box penetration test is a technical and targeted exercise that involves testing the security of a specific system or application, without any prior knowledge or access to its internal details or configuration. A black box penetration test can help to identify the vulnerabilities and weaknesses of the system or application, and to simulate the perspective and behavior of an external attacker, but it cannot test the security of the entire network or organization, or the response of the incident response team and other stakeholders to a cyber attack.

A simulated phishing exercise is a social engineering and awareness exercise that involves sending fake emails or messages to the organization’s staff, to test their ability to recognize and report phishing attempts. A simulated phishing exercise can help to measure the level of security awareness and training of the staff, and to simulate one of the most common cyber attack vectors, but it cannot test the security of the network or systems, or the response of the incident response team and other stakeholders to a cyber attack.

References = 1: What is a Red Team Exercise? | Redscan 2: Red Team vs Blue Team: How They Differ and Why You Need Both | CISA 3: Red Team Exercises: What They Are and How to Run Them | Rapid7 4: What is a Walkthrough Test? | Definition and Examples | ISACA : Penetration Testing Types: Black Box, White Box, and Gray Box | CISA