13 Jul 2026CMMC Phase II suspended: no C3PAO assessments can be designated. DFARS 7012 and Rev 2 still apply.What changed, and what did not

NIST SP 800-171 Rev 2 · 3.4 Configuration Management

3.4.8 Deny-by-exception software policy

Apply deny-by-exception (blacklisting) policy to prevent the use of unauthorized software or deny-all, permit-by-exception (whitelisting) policy to allow the execution of authorized software.
SPRS weight
5
5 points deducted from 110 when not implemented.
CMMC level
L2
Level 2 only; not among the 17 Level 1 practices.
Assessment objectives
3
From NIST SP 800-171A, each one a “determine if” an assessor answers.

What an assessor checks

NIST SP 800-171A breaks 3.4.8 into 3 objectives. Every one has to be met for the requirement to be met; a partial answer scores as not implemented.

  1. [a]Determine if a policy specifying whether whitelisting or blacklisting is to be implemented is specified.
  2. [b]Determine if the software allowed to execute under whitelisting or denied use under blacklisting is specified.
  3. [c]Determine if whitelisting to allow the execution of authorized software or blacklisting to prevent the use of unauthorized software is implemented as specified.
Examine
[SELECT FROM: Configuration management policy; procedures addressing least functionality in the system; security plan; configuration management plan; system design documentation; system configuration settings and associated documentation; list of software programs not authorized to execute on the system; list of software programs authorized to execute on the system; security configuration checklists; review and update records associated with list of authorized or unauthorized software programs; change control records; system audit logs and records; other relevant documents or records].
Interview
[SELECT FROM: Personnel with responsibilities for identifying software authorized or not authorized to execute on the system; personnel with information security responsibilities; system or network administrators].
Test
[SELECT FROM: Organizational process for identifying, reviewing, and updating programs authorized or not authorized to execute on the system; process for implementing blacklisting or whitelisting; mechanisms supporting or implementing blacklisting or whitelisting].

If it is open: POA&M eligibility

Not POA&M-eligible: above the 1-point ceiling · 5 points deducted

Worth 5 points. No requirement over 1 point may appear on a Level 2 POA&M, so this has to be closed before the assessment.

A POA&M is only permitted at a score of 88 or above, and closes in one 180-day window. Check a full gap list or compute your score.

Where 3.4.8 maps

NIST SP 800-53 Rev 5

  • CM-8 Information System Component Inventory

NIST CSF 2.0

  • Assets are identified and inventoried Asset Management
  • Configuration management processes are established Information Protection Processes and Procedures

SOC 2

No direct mapping.

Query it from your own tools

This page and the MacTech CMMC MCP server render the same dataset. Ask your assistant and it will answer from the methodology, not from memory.

lookup_control 3.4.8
get_assessment_objectives 3.4.8
generate_poam_entries ["3.4.8"]

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From MacZine

Working notes on Configuration Management

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