Cyber threats are becoming more advanced and frequent. To stay protected, organisations need strong security measures. One proven method is red teaming. The National Institute of Standards and Technology (NIST) describes it as a group authorised to copy the attack methods of a potential adversary against an organisation’s security posture.

A penetration test looks for weaknesses in systems or networks. A red team exercise goes further by simulating a real-world adversarial attack. It tests the full security setup, including technology, processes, and people. By using tactics, techniques, and procedures (TTPs) seen in genuine attacks, these simulations reveal weaknesses that other testing might miss. They also help improve detection, response, and recovery from incidents.

Understanding Red Teaming

Red teaming is a type of security testing that shows how an organisation might cope with a real attack. It covers the whole attack process, often including digital breaches, physical security checks, and social engineering.

The main aim is to see how an attacker could combine multiple weaknesses to gain access and meet their goal without being detected. This provides a clear view of the organisation’s current security posture and what needs to be improved.

Historical Background

The idea comes from military planning. In 19th-century Prussian war games, the defending side was called the blue team, and the simulated enemy was the red team. These exercises tested battle plans before any fighting took place.

During the Cold War, defence agencies used similar methods to challenge operational strategies. Businesses later applied the same thinking to prepare for competitor moves. In cybersecurity, it has developed into a structured way of testing technical defences and organisational readiness.

How an Offensive Security Team Operates

Although every simulation is different, most follow a process that copies how real attackers work.

1. Planning and Coordination

Before starting, the goals and limits of the exercise are set. For example, the aim might be to gain access to a database, bypass physical security, or extract sensitive data without triggering alarms. Rules of engagement make sure the activity is safe, controlled, and approved.

2. Reconnaissance and Intelligence Gathering

The team studies the organisation’s digital and physical setup. They may collect open-source intelligence (OSINT) from websites, social media, and public records. They can also scan for technical weaknesses and observe building entry points or staff routines. This helps identify the most likely ways in.

3. Initial Access

With the gathered information, the team attempts to get a foothold. This could involve spear phishing, exploiting unpatched software, cloning access cards, or convincing an employee to allow entry. The chosen method matches the agreed objectives and the TTPs being copied.

4. Privilege Escalation and Lateral Movement

After getting in, the aim is to increase control. This could mean moving from a basic user account to administrator level, switching between network areas, or using stolen credentials to reach important systems. This step tests how well the blue team can detect and stop suspicious activity.

5. Persistence

An attacker will often try to keep access. The team may set up backdoors, create hidden accounts, or change settings so they can return even if the first route is closed.

6. Achieving Objectives and Exfiltration

The last step is meeting the mission’s target, such as copying files, changing records, or taking control of a physical asset. In a real attack, this would cause damage. In a simulation, no harm is done, but the potential impact is shown.

7. Debrief and Reporting

The exercise ends with a detailed report for stakeholders. This includes what methods were used, where defences worked or failed, and how quickly incidents were spotted. It also gives recommendations for improving security measures.

Techniques and Procedures

An adversary simulation can use many tactics, techniques, and procedures, such as:

- Exploiting software flaws

- Using spear phishing, vishing, or other social engineering to trick staff

- Breaking physical security, like locks or RFID systems

- Combining digital and physical methods, for example, by leaving a malicious USB device inside the premises

By using these varied techniques, simulations test the organisation’s defences across multiple layers.

Red Teaming vs Penetration Testing

A penetration test is usually planned and focuses on finding as many vulnerabilities as possible within a set time and scope.

A red team exercise is mostly covert, with only a few people aware it is happening. The aim is to achieve a specific goal without being detected.

Penetration testing looks at parts of security in isolation. A red team exercise tests how the organisation as a whole,  including the blue team, responds to a realistic attack.

Blue Team and Purple Team

The blue team is responsible for spotting, stopping, and responding to attacks.

Purple teaming brings offensive and defensive teams together to share what they learn. This cooperation improves both attack and defence strategies, strengthening security operations.

Benefits of Realistic Security Testing

Simulations of this kind bring several key benefits:

- A clear view of the organisation’s security posture

- Improved incident response through realistic practice

- Clear priorities for improving security measures

- Better awareness and resilience among staff

- Evidence to meet regulatory and industry standards

Physical Security in Adversary Simulations

Security testing is not only about networks and software. Physical security is just as important. If an intruder can get inside a building, they might bypass technical defences completely.

Exercises may involve trying to enter restricted areas, testing surveillance, and checking how staff respond to unknown visitors. This ensures defences cover both digital and physical risks.

Real-World Examples

Financial institutions have found weaknesses in login systems, leading to stronger authentication and better staff training.

Healthcare providers have discovered gaps in encryption and access controls, resulting in tighter safeguards for sensitive information.

Technology companies have identified outdated security protocols that left them open to advanced persistent threats. They responded with upgraded defences and faster incident response processes.

Integrating Adversary Simulation into a Strategy

For the best results, simulations should be part of an ongoing security plan. Leadership support is essential for funding, training, and updating scenarios.

The approach works best when combined with penetration testing, blue team activities, and purple team collaboration. Scenarios should be updated to reflect current security risks and new attack methods.

Regular testing, with quick action on the results, keeps defences ready for future challenges.

Emerging Trends

Adversary simulation continues to grow, with new trends such as:

- Continuous automated testing for regular checks without heavy resources

- Testing of AI systems to find vulnerabilities and bias

- Combining cyber, physical, and social attack methods

- Industry-specific exercises for unique sector threats

Conclusion

Simulating a real-world adversarial attack gives a far deeper insight than a penetration test. It is a complete way to see how an organisation performs under pressure.

These engagements test security operations, uncover security risks, and strengthen the overall security posture. The results help prioritise investment, refine defence strategies, and build a culture of awareness.

With threats constantly evolving, regular testing and red teaming activity keep organisations prepared, resilient, and able to protect their most valuable assets.