Least privilege: a key principle for the security of the Information System

moindre privilège - least privilege

The least privilege principle consists in limiting the rights/authorizations of any individual on the information system to only those applications/data that are necessary for his missions. This principle appears in many guides relating to cybersecurity, in particular in documents published by the National Cybersecurity Agency of France – ANSSI (PA-022 – recommendations relating to the secure administration of information systems or PG-040 – recommendations for the implementation of system partitioning) or in the rules issued by the French MPL (Military Programming Law).

Benefits for the IS security

The advantages of the least privilege principle are obvious: by individualizing and limiting the data to which users have access, the risk of data leakage will be all the more limited. The same applies to applications which, by being accessible only to those who need them for their work, will be less likely to be targeted by cyber attackers.

Social engineering (manipulation of people by gaining their trust in order to retrieve information, e.g. login credentials) is a perfect example of the utility of the least privilege principle. If someone steals the identity of a user, it is possible that he will extract data or perform actions in the target organization’s applications. Thanks to this principle only those data and applications which the user who is the victim of social engineering has access to will be concerned. To gain in efficiency, the notion of least privilege must therefore be as precise as possible and, above all, regularly updated, according to the evolution of employees’ positions.

How to implement the least privilege principle?

Several tools allow CISOs or CIOs to effectively implement the least privilege principle, starting with Identity and Access Management (IAM) solutions. Indeed, they allow the management of users’ authorizations on the IS and thus the access to applications, data or privileged user accounts. The IAM solutions allow to automate certain processes, for example when changing positions, and ensure that every user has access to the applications and data they need, no more, no less.

To implement this principle for roaming employees and guarantee the security of the IS in all circumstances, organizations can choose ZTNA (Zero Trust Network Access) solutions. They are much more secure than VPNs since ZTNA gives access to an application or a resource. This allows a granularity of access while the VPN gives access to the whole network. Thus, in case of a malicious act, intentional or not, caused by the legitimate user or not, the impact will be limited only to the applications accessible by the account concerned.

When it comes to privileged accounts, the least privilege principle is all the more important since any malicious action will potentially have a significant impact on the integrity of the IS. It is therefore recommended to regularly update rights and ensure that any inactive accounts of employees who have left the company or outsourcers whose contracts have expired are deleted. PAM (Privileged Access Management) solutions can help achieve these objectives by centralizing the management of privileged accounts and the traceability of actions carried out on the IS.

By combining our solutions, Systancia Identity (IGA – Identity Governance and Access), Systancia Gate (ZTNA – Zero Trust Network Access) and Systancia Cleanroom (PAM – Privileged Access Management), it is possible to implement the least privilege principle at different levels, and raise the global level of IS security.