CM.L2-3.4.2 · NIST SP 800-171 3.4.2

Security Configuration Enforcement

Establish and enforce security configuration settings for information technology products employed in organizational systems.

5 points if not metMust be fully met, cannot POA&M2 assessment objectives

What an assessor scores, the objectives

CM.L2-3.4.2 is met only when every one of these 2 objectives, from NIST SP 800-171A, is satisfied. A single missed objective makes the whole requirement not met.

  • a.security configuration settings for information technology products employed in the system are established and included in the baseline configuration
  • b.security configuration settings for information technology products employed in the system are enforced

How a C3PAO checks it

NIST SP 800-171A defines three assessment methods. For CM.L2-3.4.2, an assessor uses these:

Examine

Configuration management policy; baseline configuration; procedures addressing configuration settings for the system; configuration management plan; system security plan; system design documentation; system configuration settings and associated documentation; security configuration checklists; evidence supporting approved deviations from established configuration settings; change control records; system audit logs and records; other relevant documents or records

Interview

Personnel with security configuration management responsibilities; personnel with information security responsibilities; system or network administrators

Test

Organizational processes for managing configuration settings; mechanisms that implement, monitor, and/or control system configuration settings; mechanisms that identify and/or document deviations from established configuration settings; processes for managing baseline configurations; mechanisms supporting configuration control of baseline configurations

What it means, in context

Configuration settings are the set of parameters that can be changed in hardware, software, or firmware components of the system that affect the security posture or functionality of the system. Information technology products for which security -related configuration settings can be defined include mainframe computers, servers, workstations, input and output devices (e.g., scanners, copiers, and pri nters), network components (e.g., firewalls, routers, gateways, voice and data switches, wireless access points, network appliances, sensors), operating systems, middleware, and applications. Security parameters are those parameters impacting the security state of systems including the parameters required to satisfy other security requirements. Security parameters include: registry settings; account, file, directory permission settings; and settings for functions, ports, protocols, and remote connections. O rganizations establish organization- wide configuration settings and subsequently derive specific configuration settings for systems. The established settings become part of the systems configuration baseline. Common secure configurations (also referred to as security configuration checklists, lockdown and hardening guides, security reference guides, security technical implementation guides) provide recognized, standardized, and established benchmarks that stipulate secure configuration settings for specific information technology platforms/products and instructions for configuring those system components to meet operational requirements. Common secure configurations can be developed by a variety of organizations including information technology product developers, manufacturers, vendors, consortia, academia, industry, federal agencies, and other organizations in the public and private sectors. NIST SP 800-70 and SP 800-128 provide guidance on security configuration settings.

Information security is an integral part of a company’s configuration management process. Security-related configuration settings are customized to satisfy the company’s security requirements and are applied them to all systems once tested and approved. The configuration settings must reflect the most restrictive settings that are appropriate for the system. Any required deviations from the baseline are reviewed, documented, and approved. Example You manage baseline configurations for your company’s systems, including those that process, store, and transmit CUI. As part of this, you download a secure configuration guide for each of your asset types (servers, workstations, network components, operating systems, middleware, and applications) from a well-known and trusted IT security organization. You then apply all of the settings that you can while still ensuring the assets can perform the role for which they are needed. Once you have the configuration settings identified and tested, you document them to ensure all applicable machines can be configured the same way [a,b]. Potential Assessment Considerations • Do security settings reflect the most restrictive settings appropriate [a]? • Are changes or deviations to security settings documented [b]?

What passing evidence looks like

The security configuration settings you enforce (the hardening choices in the baseline) and the tool screenshots proving they are applied fleet wide.

Common ways contractors fail CM.L2-3.4.2

  • !This is the enforcement half of 3.4.1. If the baseline says screen lock 15 minutes, show the Intune or GPO setting pushing it, hand configured machines drift and assessors know it.

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CM.L2-3.4.2 questions, answered

How many points is CMMC requirement CM.L2-3.4.2 worth?+

CM.L2-3.4.2 is worth 5 points in the CMMC Level 2 score under 32 CFR 170.24. If it is not met, you lose 5 from your total of 110.

Can CM.L2-3.4.2 be placed on a POA&M?+

No. CM.L2-3.4.2 must be fully met before you can file. It cannot be deferred to a POA&M, so it is a gate on your assessment.

What family does CM.L2-3.4.2 belong to?+

CM.L2-3.4.2 is in the Configuration Management (CM) family, one of the 14 families of NIST SP 800-171 that make up CMMC Level 2.

Key references
  • NIST SP 800-171 Rev. 2 3.4.2