DISCUSSION [NIST SP 800-171 R2]
This requirement establishes and maintains baseline configurations for systems and system components including for system communications and connectivity. Baseline configurations are documented, formally reviewed, and agreed-upon sets of specifications for systems or configuration items within those systems. Baseline configurations serve as a basis for future builds, releases, and changes to systems. Baseline configurations include information about system components (e.g., standard software packages installed on workstations, notebook computers, servers, network components, or mobile devices; current version numbers and update and patch information on operating systems and applications; and configuration settings and parameters), network topology, and the logical placement of those components within the system architecture. Baseline configurations of systems also reflect the current enterprise architecture. Maintaining effective baseline configurations requires creating new baselines as organizational systems change over time. Baseline configuration maintenance includes reviewing and updating the baseline configuration when changes are made based on security risks and deviations from the established baseline configuration.
Organizations can implement centralized system component inventories that include components from multiple organizational systems. In such situations, organizations ensurethat the resulting inventories include system-specific information required for proper component accountability (e.g., system association, system owner). Information deemed necessary for effective accountability of system components includes hardware inventory specifications, software license information, software version numbers, component owners, and for networked components or devices, machine names and network addresses. Inventory specifications include manufacturer, device type, model, serial number, and physical location.
NIST SP 800-128 provides guidance on security-focused configuration management.
Further Discussion
An effective cybersecurity program depends on consistent, secure system and component configuration and management. Build and configure systems from a known, secure, and approved configuration baseline. This includes:
documenting the software and configuration settings of a system;
placement within the network; and
other specifications as required by the organization.
Example
You are in charge of upgrading the computer operating systems of your office’s computers. You research how to set up and configure a workstation with the least functionality and highest security and use that as the framework for creating a configuration that minimizes functionality while still allowing users to do their tasks. After testing the new baseline on a single workstation, you document this configuration and apply it to the other computers [a]. You then check to make sure that the software changes are accurately reflected in your master system inventory [e]. Finally, you set a calendar reminder to review the baseline in three months [f].
Potential Considerations
Do baseline configurations include software versions and patch level, configuration parameters, network information, and communications with connected systems [a,b]?18
Are baseline configurations updated as needed to accommodate security risks or software changes [c]? 19
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.
NO WARRANTY. THIS MATERIAL IS FURNISHED ON AN “AS-IS” BASIS. CARNEGIE MELLON UNIVERSITY AND THE JOHNS HOPKINS UNIVERSITY APPLIED PHYSICS LABORATORY LLC MAKE NO WARRANTIES OF ANY KIND, EITHER EXPRESSED OR IMPLIED, AS TO ANY MATTER INCLUDING, BUT NOT LIMITED TO, WARRANTY OF FITNESS FOR PURPOSE OR MERCHANTABILITY, EXCLUSIVITY, OR RESULTS OBTAINED FROM USE OF THE MATERIAL NOR ANY WARRANTY OF ANY KIND WITH RESPECT TO FREEDOM FROM PATENT, TRADEMARK, OR COPYRIGHT INFRINGEMENT.