The principle of least privilege is a key concept in information security that aims to provide users with the minimum level of access—or permissions—necessary to perform their job functions. Byensuring that users only have the access they need, organizations can significantly reduce the risk associated with excessive access by authorized users.

Understanding Least Privilege

The principle of least privilege restricts access rights for users to the bare minimum permissions they need to perform their work. This minimizes the potential damage from accidents or malicious activities.

Least privilege should be applied to all user accounts, including administrative and service accounts.

Implementation

Implementing least privilege involves a detailed analysis of job functions and the necessary access required for each role.

Regularly review and update access permissions to ensure they remain aligned with current job responsibilities and organizational needs.

Mitigating Risk

By limiting access to only what is necessary, organizations can prevent users from having permissions that could be exploited, intentionally or unintentionally, to cause harm.

This also includes revoking unnecessary privileges when users change roles or no longer need access.

Comparison with Other Options

A. Monitoring user activity using security logs: While monitoring can detect inappropriate activity, it does not prevent it.

B. Revoking access for users changing roles: This is a necessary practice but does not address the initial allocation of excessive privileges.

D. Conducting periodic reviews of authorizations granted: Periodic reviews are important but are reactive rather than proactive.

References

Sybex-CISSP-Official-Study-Guide-9-Edition.pdf, p. 641, discussing the principle of least privilege and its implementation​​.