3.4.9Control what users install
Users cannot silently install whatever they find, and installs are monitored.
The requirement, verbatim
NIST SP 800-171 Rev. 2 · 3.4.9Control and monitor user-installed software.
NIST's discussion
Users can install software in organizational systems if provided the necessary privileges. To maintain control over the software installed, organizations identify permitted and prohibited actions regarding software installation through policies. Permitted software installations include updates and security patches to existing software and applications from organization-approved “app stores.” Prohibited software installations may include software with unknown or suspect pedigrees or software that organizations consider potentially malicious. The policies organizations select governing user-installed software may be organization-developed or provided by some external entity. Policy enforcement methods include procedural methods, automated methods, or both.
NIST SP 800-171 Rev. 2, discussion under 3.4.9. Whitespace normalised; wording unchanged.
Assessment objectives
An assessor decides each of these separately. The requirement is met only when every objective is.
- [a] a policy for controlling the installation of software by users is established
- [b] installation of software by users is controlled based on the established policy
- [c] installation of software by users is monitored
NIST SP 800-171A, determination statements for 3.4.9.
For assessors: examine, interview, test
NIST SP 800-171A names what an assessor may examine, whom they may interview, and what they may test for this requirement. Assessors select from these lists; they are not a checklist of everything you must produce.
Examine
- Configuration management policy
- procedures addressing user installed software
- configuration management plan
- system security plan
- system design documentation
- system configuration settings and associated documentation
- list of rules governing user-installed software
- system monitoring records
- system audit logs and records
- continuous monitoring strategy
- other relevant documents or records
Interview
- Personnel with responsibilities for governing user-installed software
- personnel operating, using, or maintaining the system
- personnel monitoring compliance with user-installed software policy
- personnel with information security responsibilities
- system or network administrators
Test
- Organizational processes governing user-installed software on the system
- mechanisms enforcing rules or methods for governing the installation of software by users
- mechanisms monitoring policy compliance
NIST SP 800-171A, potential assessment methods and objects for 3.4.9.
Evidence
No evidence examples are published for this requirement yet. The objectives above are what an assessor checks; evidence is whatever shows each one is true in your environment, dated and kept with your system security plan.
Scoring weight
Worth 1 point. Not meeting this requirement subtracts 1 from your 110-point SPRS score.
DoD NIST SP 800-171 Assessment Methodology v1.2.1 weighting, as carried in the Bedrock scoring table. The score starts at 110 and subtracts the weight of every requirement not met.
In Rev. 3
Rev. 2 is what your contract requires today. A standing DoD class deviation keeps Rev. 2 in force; NIST has published Rev. 3, but it is not adopted for contracts. In Rev. 3 this requirement is withdrawn and incorporated elsewhere: 03.01.05 Least Privilege, 03.01.06 Least Privilege – Privileged Accounts, 03.01.07 Least Privilege – Privileged Functions, 03.04.08 Authorized Software – Allow by Exception, 03.12.03 Continuous Monitoring.
See the Rev. 2 and Rev. 3 wording word by word, or start with the status page.
Related requirements
Where this page's facts come from
- Requirement text
- bedrock-cmmc-api@89b8e8e:migrations/004_reference_requirements.sql#Requirement.basicRequirement@rev2
- Discussion
- bedrock-cmmc-api@89b8e8e:migrations/004_reference_requirements.sql#Requirement.discussion@rev2
- Practice name
- bedrock-cmmc-api@89b8e8e:migrations/004_reference_requirements.sql#Requirement.title@rev2 (CMMC Assessment Guide practice name)
- Objectives
- bedrock-cmmc-api@89b8e8e:migrations/005_reference_objectives.sql#AssessmentObjective.description@rev2
- Examine, interview, test
- bedrock-cmmc-api@89b8e8e:migrations/005_reference_objectives.sql#AssessmentObjective.description@rev2 ({examineGuidance, interviewGuidance, testGuidance})
- Level
- bedrock-cmmc-api@89b8e8e:migrations/021_fix_level1_requirements.sql#Requirement.cmmcLevel@rev2
- Weight
- bedrock-cmmc-api@89b8e8e:internal/cmmc/requirement_values.go#requirementValues (DoD AM v1.2.1 / eMASS L2 template v3.8)
- Rev. 3 mapping
- bedrock-cmmc-api@89b8e8e:docs/reference/nist-800-171-rev3/normalized/r2_r3_transition_map.json#r2_to_r3
- Plain-language title and summary
- editorial/CMMC Navigator.dc.html#RAW (Foxx Cyber editorial)