DISCUSSION [NIST SP 800-171 R2]
Organizations employ the principle of least privilege for specific duties and authorized accesses for users and processes. The principle of least privilege is applied with the goal of authorized privileges no higher than necessary to accomplish required organizational missions or business functions. Organizations consider the creation of additional processes, roles, and system accounts as necessary, to achieve least privilege. Organizations also apply least privilege to the development, implementation, and operation of organizational systems. Security functions include establishing system accounts, setting events to be logged, setting
intrusion detection parameters, and configuring access authorizations (i.e., permissions, privileges).
Privileged accounts, including super user accounts, are typically described as system administrator for various types of commercial off-the-shelf operating systems. Restricting privileged accounts to specific personnel or roles prevents day-to-day users from having access to privileged information or functions. Organizations may differentiate in the application of this requirement between allowed privileges for local accounts and for domain accounts provided organizations retain the ability to control system configurations for key
security parameters and as otherwise necessary to sufficiently mitigate risk.
Further Discussion
The principle of least privilege applies to all users and processes on all systems, but it is critical to systems containing or accessing CUI. Least privilege:
restricts user access to only the machines and information needed to fulfill job responsibilities; and
limits what system configuration settings users can change, only allowing individuals with a business need to change them.
Example 1
As a system administrator, you create accounts. By default, everyone is assigned a basic user role, which prevents a user from modifying system configurations. Privileged access is only assigned to users and processes that require it to carry out job functions, such as IT staff, and is very selectively granted [b,d].
Potential Considerations
Are privileged accounts documented and is when they may be used defined [a]?
Are users assigned privileged accounts to perform their job functions only when it is necessary [b]?
Are necessary security functions identified (e.g., access control configuration, system configuration settings, or privileged account lists) that must be managed through the use of privileged accounts [c]?
Is access to privileged functions and security information restricted to authorized employees [d]?6
Copyright
Copyright 2020, 2021 Carnegie Mellon University and The Johns Hopkins University Applied Physics Laboratory LLC.
Copyright 2021 Futures, Inc.
This material is based upon work funded and supported by the Department of Defense under Contract No. FA8702-15-D-0002 with Carnegie Mellon University for the operation of the Software Engineering Institute, a federally funded research and development center, and under Contract No. HQ0034-13-D-0003 and Contract No. N00024-13-D-6400 with the Johns Hopkins University Applied Physics Laboratory LLC, a University Affiliated Research Center.
The view, opinions, and/or findings contained in this material are those of the author(s) and should not be construed as an official Government position, policy, or decision, unless designated by other documentation.
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