Least Privilege (Principle of Least Privilege)

Least Privilege, the principle of least privilege, is a security principle according to which every identity receives only the permissions it actually needs for its current task – as limited as possible in scope and duration. It applies equally to employees, administrators, applications, service accounts and other technical identities.

The principle goes back to fundamental work on information security from the 1970s and is now anchored in numerous standards, for example as control AC-6 in the NIST control catalog SP 800-53 and in the access rights controls of ISO/IEC 27001. In practice, least privilege requires clearly defined roles, the consistent revocation of rights that are no longer needed and regular reviews. The central benefit lies in damage limitation: if an account is compromised, the attacker only obtains its narrowly limited rights.

For privileged accounts, Privileged Access Management (PAM) implements the principle technically; it is sharpened in time by Just-in-Time Access (JIT), where rights exist only for the duration of a task. Least privilege is also a core principle of Zero Trust, because there no identity is trusted by default and every access is limited to the necessary extent.