Purple Teaming – Guidance through the pouring rain
There is growing talk in cyber security circles of a technique called “purple teaming”. The benefits sit beside red teaming and blue teaming in the emerging discourse.
But purple teaming isn’t a form of security assessment espoused by Prince or Jimi Hendrix, there is no haze or rain. Instead, it’s a new way of looking at security assurance as a collaborative process between attacker-centric and defender-centric security teams.
Red Teams …
Red teams, or red teaming, is used to describe a security assessment approach that a hacker would adopt. Looking for weaknesses, vulnerabilities, misconfigurations to exploit; rattling every window and testing every door.
Typically, it would start with external fact finding and reconnaissance, followed by probing using viable/exploitable attack scenarios to see how far an attacker could get; what they could access, what systems and data are at risk.
It’s an internally run, external penetration test, if you will. A group set on looking inwards from the outside. A penetration test is a commissioned service, normally scheduled and with terms of reference. A red team, on the other hand, needs to be free to adopt an unrestricted set of tactics, techniques and procedures in an effort to access the enterprise (including physical access). It must be able to operate without warning. Hence it is, in part, testing the defender’s ability to detect and respond.
If you want to read more (including the military origin of the term) as usual Wikipedia is your friend.
Blue teams …
Blue teams, on the other hand, are defenders. They are about establishing the effectiveness of controls and validating security settings “from within”. Thinking like the enemy, attending to any unlocked windows or doors. They have a proactive mindset, bent on the improvement of security defence and response efforts. They examine systems, networks, controls, records to make sure everything is set right and protected. In addition, they are deliberately on the receiving end of red team attacks to test detection and defence strategies.
Clearly, the brief for the internal team is to continuously assess the posture of the environment. Like commissioning a security audit or a health check, it’s like seeking the expertise of a consultancy or expert service provider.
Once again, the Wikipedia definition is worth a read.
Purple teams …
Oddly, a purple team or purple teaming is not really about a team at all. It’s about the cooperation of an enterprise’s red and blue teams working together to build an improved overall cyber posture.
Like the colour purple suggests, it is a mindset of having the blue and red teams work together collaboratively to find security issues and fix them – blending the techniques of an attacker and a defender. This might be in part an iterative process: with the red team identifying issues, possible weaknesses or perceived avenues of attack; while the blue team proactively responds with efforts to mitigate threats and resolve any weaknesses. With a combined effort, by both teams, improvement in the posture of the organisation results.
The goal is to hone the blue team’s work to enable the organisation to better defend against a fully capable adversary. So that even an attacker that might have inside knowledge about the internal systems and their security, can be thwarted by the network defenders whose efforts in conjunction with the red team, are fully across the types of techniques and exploits an external attacker might employ.
Blue teams can go as far as flagging known issues, so the red team can focus on testing mitigation efforts rather than wasting time trying every single possible vulnerability without success. Hence, it’s not a purple team, but a collaboration of red and blue teams. So perhaps a little bit purple hazy after all.
The important thing here is that the use of smart security risk management tools, like Huntsman Security’s Essential 8 Auditor and SmartCheck for Ransomware, can certainly support a purple mindset. By automatically reporting on your security posture and identifying any gaps, your organisation can obtain a deep understanding of the state of its security controls, the effectiveness of their operation and the risk exposures that might remain.