AC-6: Least Privilege
Control Family:
CSF v2.0 References:
Threats Addressed:
Baselines:
Previous Version:
- NIST Special Publication 800-53 Revision 4:
- AC-6: Least Privilege
Control Statement
Employ the principle of least privilege, allowing only authorized accesses for users (or processes acting on behalf of users) that are necessary to accomplish assigned organizational tasks.
Supplemental Guidance
Organizations employ least privilege for specific duties and systems. The principle of least privilege is also applied to system processes, ensuring that the processes have access to systems and operate at privilege levels no higher than necessary to accomplish organizational missions or business functions. Organizations consider the creation of additional processes, roles, and accounts as necessary to achieve least privilege. Organizations apply least privilege to the development, implementation, and operation of organizational systems.
OT Discussion
Example compensating controls include providing increased personnel security and auditing. The organization carefully considers the appropriateness of a single individual having multiple critical privileges. System privilege models may be tailored to enforce integrity and availability (e.g., lower privileges include read access, and higher privileges include write access).
Control Enhancements
AC-6(1): Authorize Access to Security Functions
Baseline(s):
- Moderate
- High
- OT Moderate (SP 800-82r3)
- OT High (SP 800-82r3)
Authorize access for [Assignment: organization-defined individuals and roles] to: [Assignment: organization-defined security functions (deployed in hardware, software, and firmware)] ; and [Assignment: organization-defined security-relevant information].
AC-6(2): Non-privileged Access for Nonsecurity Functions
Baseline(s):
- Moderate
- High
- OT Moderate (SP 800-82r3)
- OT High (SP 800-82r3)
Require that users of system accounts (or roles) with access to [Assignment: organization-defined security functions or security-relevant information] use non-privileged accounts or roles, when accessing nonsecurity functions.
AC-6(3): Network Access to Privileged Commands
Baseline(s):
- High
- OT High (SP 800-82r3)
Authorize network access to [Assignment: organization-defined privileged commands] only for [Assignment: organization-defined compelling operational needs] and document the rationale for such access in the security plan for the system.
AC-6(4): Separate Processing Domains
Baseline(s):
Provide separate processing domains to enable finer-grained allocation of user privileges.
AC-6(5): Privileged Accounts
Baseline(s):
- Moderate
- High
- OT Moderate (SP 800-82r3)
- OT High (SP 800-82r3)
Restrict privileged accounts on the system to [Assignment: organization-defined personnel or roles].
AC-6(6): Privileged Access by Non-organizational Users
Baseline(s):
Prohibit privileged access to the system by non-organizational users.
AC-6(7): Review of User Privileges
Baseline(s):
- Moderate
- High
- OT Moderate (SP 800-82r3)
- OT High (SP 800-82r3)
Review [Assignment: organization-defined frequency] the privileges assigned to [Assignment: organization-defined roles and classes] to validate the need for such privileges; and Reassign or remove privileges, if necessary, to correctly reflect organizational mission and business needs.
AC-6(8): Privilege Levels for Code Execution
Baseline(s):
Prevent the following software from executing at higher privilege levels than users executing the software: [Assignment: organization-defined software].
AC-6(9): Log Use of Privileged Functions
Baseline(s):
- Moderate
- High
- OT Moderate (SP 800-82r3)
- OT High (SP 800-82r3)
Log the execution of privileged functions.
AC-6(10): Prohibit Non-privileged Users from Executing Privileged Functions
Baseline(s):
- Moderate
- High
- OT Moderate (SP 800-82r3)
- OT High (SP 800-82r3)
Prevent non-privileged users from executing privileged functions.