NIST 800-171 3.14.3 (SI.L2-3.14.3): Security Advisories

Monitor system security alerts and advisories and take action in response.

NIST SP 800-171 Rev. 2, requirement 3.14.3

CMMC Level 2 practice SI.L2-3.14.3Published 2026-11-11

What 3.14.3 means in practice

Someone watches security alerts and advisories, from vendors, from CISA and from your own tools, decides what each one means for your systems, and acts on it. Keep evidence of the sources you follow and the actions you took.

SPRS points and the CMMC POA&M

CMMC Level 2 practice: SI.L2-3.14.3
SPRS points: 5 points. When it is not met, the DoD Assessment Methodology subtracts 5 from the score of 110.
CMMC POA&M: Not allowed. It is worth 5 points, and 32 CFR 170.21(a)(2)(ii) admits only requirements worth 1 point, with one exception: 3.13.11 when encryption is used but not FIPS validated.

Sources: NIST SP 800-171 DoD Assessment Methodology, version 1.2.1 (June 24, 2020), Annex A; 32 CFR 170.21, Plan of Action and Milestones requirements.

What an assessor checks for 3.14.3

NIST SP 800-171A gives 3 determination statements for 3.14.3, each found satisfied or other than satisfied. Determine if:

3.14.3[a] response actions to system security alerts and advisories are identified.
3.14.3[b] system security alerts and advisories are monitored.
3.14.3[c] actions in response to system security alerts and advisories are taken.

NIST SP 800-171A (June 2018), assessment objectives for 3.14.3

Evidence that shows 3.14.3 is met

The sources of alerts and advisories you subscribe to.
The procedure for assessing them and responding.
Records of advisories received and the actions taken.

How PolicyCortex gathers the evidence

PolicyCortex reads this evidence with the collectors below, read only, and grades 3.14.3 from it. Each line says what the product checks.

Microsoft Defender for Cloud: Secure score and security contacts. Checks that Microsoft Defender for Cloud has a security contact set to receive alerts.
Microsoft Defender for Cloud: Security alerts. Checks that no high or critical Defender security alert stays unresolved.

Related pages

Calculator: SPRS score calculator: mark 3.14.3 and the other 109 requirements and see the score.
Sample package: Sample package: an SSP, a POA&M and an evidence chain the product generated from demonstration data.
Family: All 7 System and Information Integrity requirements (3.14).
Previous: 3.14.2: Malware Protection
Next: 3.14.4: Malware Updates
All requirements: All 110 NIST SP 800-171 requirements, by family.

Related records

Guides and articles describe the work. The evidence that work produces is described in three proof pages, the architecture page, and the two pages on authorization.

proof.state: Proof of State. What the environment was, as of a date someone else picks: point-in-time records, content hashed and chained.
proof.change: Proof of Change. Who or what altered the environment, under what authority, with before and after state hashes.
proof.agency: Proof of Agency. What a machine was permitted to do before it acted, what it did, and what would have stopped it.
architecture: Architecture. How the chain is built and where the evidence is stored in each delivery mode.
authorization: Continuous ATO. How an authorizing official's decision is recorded with its package, and how the authorized system is checked against it every hour.
baseline: NIST SP 800-53. The Low, Moderate and High baselines as evidence, with the SSP, SAR and POA&M generated from one record.