What is Least Privilege Access

Least Privilege Access (LPA), commonly referred to as the Principle of Least Privilege (PoLP), is a core and irrefutable principle of cybersecurity that states that all users, applications, services, devices, and non-human identities (NHI) in an organization should be given only the minimum set of access permissions that allow it to perform its legitimate, authorized functions - no more and no less. It is the digital equivalent of only giving someone the exact keys to open the doors required to complete the job.

This principle contrasts with the traditional practice of granting access broadly "just in case" or fully granting permissions for expediency. Rather, LPA requires a precise, granular, and dynamic access approach. LPA works on the premise that more access than what is strictly necessary to perform an action = some risk, vulnerability, and expanded target for attack.

LPA in Practice: Why is Least Privilege Necessary

Applying LPA requires an understanding of roles, responsibilities, and the work to be done by different entities.

• Users: An accountant does not need administrator access to production servers. A marketing specialist does not need access to sensitive HR files.

• Applications: An application consuming public content from a website does not need write access to a critical financial database.

• Services: A service that runs in the background does not need permissions that allow it to take actions other than the required function (e.g., a service can read log files but cannot reconfigure system settings).

• Devices: An IoT device should only be able to communicate with its intended controller and not the entire internal network.

• Non-Human Identities (NHIs) / Machine Identities: A systems AI that will only analyze customer support tickets does not need access to change the core database schema at all. They only need a key with access to the specific API endpoints for interacting with data.

LPA is implemented with different access control models:

• Role-Based Access Control (RBAC): Users are assigned to roles and roles have defined access. LPA ensures that the user access roles are as narrow as possible.

• Attribute-Based Access Control (ABAC): Access is granted to data based on user, resource, and environmental attributes that can allow more dynamic and granular access.

• Policy-Based Access Control (PBAC): Policies define what access is allowed based on conditions and can take an RBAC or ABAC approach.

Advantages of Least Privilege Access

Least Privilege Access is more than a theoretical goal. It is a practical and highly effective security control that stops a significantly greater amount of risk across the organization. It is a foundation to truly building out a mature cyber resilience posture.

Now let's look at why adopting Least Privilege Access is utterly essential for modern enterprises:

• Significantly Limit the Attack Surface: Creating less unused access will limit the entries by attackers while also limiting the potential exploitable paths. Every unused privilege is essentially a back door.

• Contain Breaches and Lateral Moves: This is the most significant advantage. When an attacker compromises an account or system user utilizing LPA, their lateral movement and access to additional sensitive resources are significantly limited, meaning the blast radius of the breach is limited.

• Mitigates Insider Threats: Whether malicious or accidental, insider actions are limited. An employee with access limited to the need cannot accidentally (or maliciously) access or compromise systems or data outside of their authorized access.

• Prevents Privilege Escalation: Often attackers are trying to gain a foothold with low-level access and then escalate privileges where possible. LPA makes this hard because the excess privileges that an attacker might exploit will be severely limited or non-existent.

• Enhances Compliance: Many, many (NIST, GDPR, HIPAA, SOX, PCI DSS, ISO 27001) industry regulations and compliance frameworks have requirements that direct and indirect use the Principle of Least Privilege Access as a security theme. LPA framework provides the enforceable principle of control, and robust auditability to demonstrate compliance, helping to avoid significant fines

• Enhances Auditability and Accountability: In a LPA world, trust is dead; every access grant can and will be justified based on a role or task. If we only allow and log limited access, less access to all parts of the environment must be searched to find who was where, when, and why, so audits will be much easier to complete and if necessary, forensics would be simpler.

• Addresses Privilege Creep: Employees change roles, projects, technology, etc. and not all permissions associated with their original role or task have been revoked. LPA, and for good measure with IGA and regular User Access Reviews (UARs) actively discover privilege creep and remediates disappearing privileges.

• Secures Non-Human Identities (NHI): The world of automation with implementing unattended processes, applications, and Agent AI is prohibitive. Often, NHIs have very sensitive privileges. LPA is both needed and important to make sure that NHIs have only the specific access privileges, only for the specified time to only accomplish the assigned automated activity. LPA has close tie-ins with Just-In-Time (JIT) Access and Zero Standing Privileges (ZSP) based program concepts.

• LPA is a founding pillar in any Zero Trust Access architecture; if you only have in authorized authenticated access to fulfill one or more work tasks, then LPA limits that a trusted identity only has as much access as necessary, be it a millisecond or 1 hour of authorized access time related to completing a task.

At ReShield we embody the Principle of Least Privilege Access as an advanced Identity and Access Management (IAM), Privileged Access Management (PAM), and Identity Governance and Administration (IGA) technology company.

The ReShield platform helps organizations successfully define, enforce, and continuously monitor Least Privilege Access for all human and machine identities in fully hybrid, and multi-cloud environments; ensuring security of the organization, compliance whenever possible within the organization, and protection against identity-based threats.