Red Team, Blue Team, Purple Team: How do simulated attacks strengthen a company’s cyber resilience?

In the world of cyber security, there has always been a division between two sides of the barricade: attackers and defenders. From this natural division, the concept of testing security through controlled confrontation was born. On one side we have the Blue Team – an in-house security team (SOC) that builds and operates defense systems on a daily basis. On the other, the Red Team – a group of ethical hackers tasked with thinking and acting like the real enemy to test the effectiveness of these defenses. For years, the model resembled a boxing sparring match that ended with a judge’s verdict, often in the form of a comprehensive report delivered weeks after the “fight.”

But what if, instead of a one-time verdict, the goal became maximizing learning and improving technique in real time? Imagine that after each round of sparring, both fighters sit down with their coach to analyze every punch delivered, every successful guard and every gap in defense. This is the revolutionary idea behind Purple Teaming. It’s a philosophy that replaces traditional confrontation with close cooperation, turning an attack simulation into an interactive, highly valuable training session. It’s an approach that makes it possible to realistically and measurably improve an organization’s resilience, instead of merely pointing out its weaknesses.

What are Red Team and Blue Team exercises in the context of cyber security?

The “Red Team” and “Blue Team” terminology originated from military exercises, where one team (red) simulated enemy forces and the other (blue) simulated their own forces. In cyber security, this concept has been adapted directly, laying the foundation for realistic security testing.

Blue Team is a team of defenders. In practice, it is simply the day-to-day name for the team responsible for a company’s operational security – most often the Security Operations Center (SOC), but can also include system administrators, network engineers and other IT professionals. Their job is to configure and maintain defense tools (SIEM, EDR, firewall), monitor alerts, respond to incidents and generally strengthen the organization’s security posture.

Red Team is a team of attackers. It is a group of ethical hackers tasked with simulating the actions, tactics and procedures (TTPs) of real-world cybercriminals in order to test the Blue Team’s defensive capabilities. Unlike standard penetration testing, the Red Team’s goal is not to find as many vulnerabilities as possible, but to conduct a realistic, often multi-stage attack to verify that the company’s detection and response mechanisms are working effectively.

What are the main goals and objectives of the Blue Team, or internal defenders?

Blue Team’s main mission is to ensure the continuous and effective protection of the organization’s digital assets. Its tasks can be divided into several key areas, which together form a comprehensive defense strategy.

Prevention: The first goal is to prevent incidents before they happen. This includes measures such as hardening (hardening) systems, managing vulnerabilities and regularly deploying security patches, configuring firewalls and antivirus systems, and educating employees on cyber hygiene.

Detection: Since 100 percent prevention is impossible, a key task is to detect as soon as possible that an intrusion has occurred. To this end, Blue Team implements and monitors a wide range of tools such as SIEM, EDR and NDR, creates detection rules, analyzes logs and looks for anomalies that could indicate malicious activity.

Response: Once an incident is detected, the Blue Team is responsible for handling it quickly and effectively. This includes analyzing the threat, stopping its spread (e.g., by isolating systems), removing the malware and restoring normal operation of systems. The team is also responsible for post-incident analysis and lessons learned for the future.

What role does the Red Team play and why does it simulate the actions of real hackers?

The Red Team’s role goes far beyond simply scanning for vulnerabilities. Its job is to think and act like a real, motivated adversary to realistically test an organization’s entire defense system – not just the technology, but also the people and processes. Red Team provides the answer to a key question that no automated scanner can provide: “Are we able to detect and stop a viable, advanced attack?”.

The Red Team, instead of looking for all possible holes in the fence, chooses one promising attack path and tries to achieve a specific, defined goal (e.g. “gain access to a customer database” or “take control of a domain controller”). In its operations, it emulates the Tactics, Techniques and Procedures (TTPs) of well-known hacking groups (e.g., APT groups), using the MITRE ATT&CK framework as a roadmap.

The purpose of such a simulation is to verify the effectiveness of the entire defense chain. Did the EDR system detect the credential theft attempt? Did the SOC analyst correctly interpret the alert? Was the incident response procedure activated in time? Red Team is a mirror that mercilessly shows where the theory and marketing promises of the tools fall short of the brutal reality.

How does a Red Team operation differ from a standard penetration test?

Although the two terms are often used interchangeably, a Red Team operation and a penetration test are two different types of exercises with different objectives and methodologies. Understanding this difference is key to choosing the right test for your organization.

A penetration test (pentest) aims to identify and exploit as many technical vulnerabilities as possible within a defined, limited scope (e.g., in a single web application or a specific network segment). Pentesters typically operate within a short, predetermined timeframe, and their goal is to provide a comprehensive list of vulnerabilities found, along with recommendations for fixing them. Pentest answers the question, “What holes do we have?”

A Red Team operation is designed to realistically simulate an adversary’s operations to test detection and response capabilities (people, processes and technology). The scope is usually very broad (the entire organization) and the duration much longer (weeks or months). Red Team tries to avoid detection and operate quietly, often using only one or two vulnerabilities to get in. A Red Team operation answers the question, “Can we detect and stop a determined enemy?”

What is the Purple Team concept and why is it not a separate team?

The traditional model, in which the Red Team launches an attack and the Blue Team tries to detect it, often ends with a report delivered weeks later. This leads to a long feedback loop and loss of valuable context. Purple Team is a philosophy that aims to solve this problem by creating an instant, collaborative feedback loop between attackers and defenders.

It is crucial to understand that the Purple Team is not a third, separate team, but a function or process that connects the Red and Blue Teams in real time. It’s a kind of “bridge” or “workshop session” where the two sides work together to achieve a common goal: improving detection and response capabilities. The color purple (purple) symbolically arises from the mixing of red (offense) and blue (defense).

In the Purple Team model, the goal is not to “win” one side. The goal is to learn together. Red Team does not try to hide its actions at all costs. Instead, it executes more attack techniques and works with the Blue Team on an ongoing basis to verify whether a technique was detected, what alerts it generated and how detection rules can be improved to make the alert more accurate next time.

What does a Purple Team exercise look like in practice?

The Purple Team exercise is a structured, interactive session that typically follows the following pattern:

1. Planning and definition of objectives: The Red Team and Blue Team jointly determine what techniques (usually from the MITRE ATT&CK framework) will be tested. For example, the goal may be to verify the ability to detect various credential theft methods.
2. Launching the simulation: Both teams sit “in the same room” (physically or virtually). Red Team announces: “OK, now I’m performing technique T1003.001 – OS Credential Dumping: LSASS Memory”. Then, using a specific tool, it carries out a simulated attack.
3. Joint analysis (the “Purple” phase): At this point, the Blue Team checks its consoles (SIEM, EDR) and responds: “We see alert X from the EDR system, but it is low priority and lacks context” or “We see absolutely nothing.”
4. Improving detection: Joint work begins. Analysts from both teams together analyze what traces (logs, events) the attack left behind. Based on this, the Blue Team (or SOC engineer) live modifies or creates a new detection rule in the SIEM/EDR system.
5. Re-testing: Red Team performs the same technique again to verify that the new rule worked correctly and generated a precise, context-rich alert.
6. Repeat cycle: the process is repeated for the next scheduled techniques.

As a result, after a Purple Team session lasting several hours, the organization leaves not with a report it will read in a month, but with a dozen new, battle-tested detection rules that realistically strengthen its defenses.

How does nFlo help organizations conduct advanced Purple Team attack simulations and exercises?

At nFlo, we believe that security testing should deliver real, measurable value and directly translate into enhanced resilience. That’s why our services in this area go far beyond standard testing, offering a mature and strategic collaborative approach.

We offer world-class Red Teaming services, during which our team of experts, using the latest threat data and the MITRE ATT&CK framework, conducts realistic simulations of adversary operations. The goal of our operations is not only to find vulnerabilities, but more importantly to provide management and technical teams with invaluable insights into how their organization realistically performs against a determined adversary.

What sets us apart is our ability to act as facilitators of Purple Team exercises. We understand that the greatest value comes from collaboration. As part of this service, our Red Team works hand-in-hand with the client’s internal security team (Blue Team). We act as a “coach” that not only tests defenses, but more importantly helps improve them in real time. We conduct structured workshop sessions where we jointly analyze each attack technique and immediately build or tune the appropriate detection mechanisms. This approach reflects our fundamental value – a partnership where the goal is not to audit, but to build cyber resilience together.