Security professionals are always on the lookout for new principles and frameworks to control and track application and service authentication and access within an enterprise network. Because of this, the zero-trust framework and the principle of least privilege, or POLP, are always top of mind.
While some may use the terms interchangeably, there are distinct differences between the two.
Principle of least privilege: A strict focus on resource access
With POLP, security administrators restrict the types of applications and resources a particular user or device can access until they successfully authenticate onto a network. The concept of this is simple: Only provide access if the user or device absolutely requires it. Thus, administrators are providing the least amount of access privilege possible.
The reasoning behind POLP is that, if any one user account is compromised — or if an employee went rogue — least privilege significantly shrinks what networked systems a malicious actor could potentially breach. Plus, limiting the scope of access restricts wide-range lateral movement throughout the network.
POLP is especially important for IT systems administrators. Prior to POLP, it was common for admins to have far greater access to systems than was required. Admins should never be allowed to log in using an account with full domain access, for example. Using POLP to restrict this access prevents a security breach from crossing over to other parts of the network.
Zero trust: Authorization and access control
The zero-trust concept takes one step back from POLP to address user/device authentication and authorization, in addition to access control. This includes the need to implement mechanisms that can accurately identify who or what is attempting to gain access and if the access behavior is odd or veers from normal activity. Authentication and authorization posture checks are performed continuously — meaning that trust is constantly verified and reverified.
It’s important to note that zero trust isn’t solely about authentication and access controls for end users and end devices. The principles and methods proposed in the zero-trust philosophy can and should extend to the data center.
In this setting, a security administrator’s goal is to verify that communications between servers in a distributed workload architecture should occur. This includes continuously verifying each system, along with restricting communications of the server application to only those deemed necessary.