---
title: "NIST 800-171 3.14.5 (SI.L2-3.14.5): Malware Scanning"
description: "NIST SP 800-171 3.14.5 Malware Scanning: 3 SPRS points, not allowed on a CMMC POA&M. The text, what assessors check and the evidence."
url: https://policycortex.com/nist-800-171/system-and-information-integrity/3.14.5
sealed: 2026-11-11
amended: 2026-11-11
register: nist-800-171/system-and-information-integrity/3.14.5
records: 7
digest: sha3:8ead05fdd3d65ab357b488a802a9e4ae86cd5add40b2bb39f68b3be29fafeb4a
---

# NIST 800-171 3.14.5 (SI.L2-3.14.5): Malware Scanning

NIST 800-171 / System and Information Integrity / 3.14.5

"Perform periodic scans of organizational systems and real-time scans of files from external sources as files are downloaded, opened, or executed." ([NIST SP 800-171 Rev. 2, requirement 3.14.5](https://doi.org/10.6028/NIST.SP.800-171r2))

CMMC Level 2 practice SI.L2-3.14.5.

## What 3.14.5 means in practice

Two kinds of scanning are required: periodic scans of systems on a defined schedule, and real-time scans of files from outside as they are downloaded, opened or run. Endpoint protection usually does both once it is configured to.

## SPRS points and the CMMC POA&M

- **CMMC Level 2 practice**: SI.L2-3.14.5
- **SPRS points**: 3 points. When it is not met, the DoD Assessment Methodology subtracts 3 from the score of 110.
- **CMMC POA&M**: Not allowed. It is worth 3 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](https://www.acq.osd.mil/asda/dpc/cp/cyber/docs/safeguarding/NIST-SP-800-171-Assessment-Methodology-Version-1.2.1-6.24.2020.pdf); [32 CFR 170.21, Plan of Action and Milestones requirements](https://www.ecfr.gov/current/title-32/section-170.21).

## What an assessor checks for 3.14.5

NIST SP 800-171A gives 3 determination statements for 3.14.5, each found satisfied or other than satisfied. Determine if:

- 3.14.5[a] the frequency for malicious code scans is defined.
- 3.14.5[b] malicious code scans are performed with the defined frequency.
- 3.14.5[c] real-time malicious code scans of files from external sources as files are downloaded, opened, or executed are performed.

[NIST SP 800-171A (June 2018), assessment objectives for 3.14.5](https://doi.org/10.6028/NIST.SP.800-171A)

## Evidence that shows 3.14.5 is met

- The defined scan frequency.
- Endpoint protection settings for scheduled and real-time scanning.
- Scan history reports.

## How PolicyCortex gathers the evidence

PolicyCortex reads this evidence with the collectors below, read only, and grades 3.14.5 from it. Each line says what the product checks.

- **Microsoft Defender for Cloud: Secure score and security contacts.** Checks that Microsoft Defender protection is on for every endpoint and that real-time scanning is enabled.

## Related pages

- **Calculator**: [SPRS score calculator: mark 3.14.5 and the other 109 requirements and see the score.](https://policycortex.com/sprs-score-calculator#family-SI)
- **Sample package**: [Sample package: an SSP, a POA&M and an evidence chain the product generated from demonstration data.](https://policycortex.com/sample-package)
- **Family**: [All 7 System and Information Integrity requirements (3.14).](https://policycortex.com/nist-800-171/system-and-information-integrity)
- **Previous**: [3.14.4: Malware Updates](https://policycortex.com/nist-800-171/system-and-information-integrity/3.14.4)
- **Next**: [3.14.6: Attack Monitoring](https://policycortex.com/nist-800-171/system-and-information-integrity/3.14.6)
- **All requirements**: [All 110 NIST SP 800-171 requirements, by family.](https://policycortex.com/nist-800-171)

Meet the requirement once. Keep the evidence current. [Request Access](https://app.policycortex.com/auth?mode=request-access) · [Book a call](https://policycortex.com/book)

## Register colophon

| Seq | Label | SHA3-256 | Prev |
|---|---|---|---|
| REC 0000 | REQUIREMENT | 79c34debeb4f | 04635e4dcc96 |
| REC 0001 | MEANING | aa8a0f79f4ce | 79c34debeb4f |
| REC 0002 | POINTS AND POA&M | 4503a14454db | aa8a0f79f4ce |
| REC 0003 | ASSESSMENT OBJECTIVES | 2dc63695c082 | 4503a14454db |
| REC 0004 | EVIDENCE | a40bc25289c8 | 2dc63695c082 |
| REC 0005 | COLLECTORS | 42f03d693c39 | a40bc25289c8 |
| REC 0006 | RELATED | 8ead05fdd3d6 | 42f03d693c39 |

Head sha3:8ead05fdd3d65ab357b488a802a9e4ae86cd5add40b2bb39f68b3be29fafeb4a. Each digest is SHA3-256 over the previous digest, the register key, the record label, and the record copy; a second party can recompute it from this document.