# NIST SP 800-53 Rev. 5 SC-18 — Mobile Code

- Source: https://support.icompaas.com/compliance/nist-sp-800-53-rev-5/sc-18-mobile-code
- Section: [Compliance](https://support.icompaas.com/compliance) › [NIST SP 800-53 Rev. 5 Controls](https://support.icompaas.com/compliance/nist-sp-800-53-rev-5) › SC — System and Communications Protection
- Last updated: 2026-06-05
- Publisher: iCompaas, Inc. (https://www.icompaas.com)

**NIST SP 800-53 Rev. 5**·Control `SC-18`·high·Component: **System and Communications Protection**

## What this control requires

> Define acceptable and unacceptable mobile code and mobile code technologies. Authorize, monitor, and control the use of mobile code within the system. Mobile code includes any program or content that can be transmitted across a network and executed on a remote system, such as Java applets, JavaScript, HTML5, WebGL, and VBScript. Guidelines ensure that mobile code does not cause damage to systems, including requiring digital signatures from trusted sources for code used within organizational systems. This control supports the Mobile Code Management System capability within the System and Communications Protection family.
> 
> — NIST SP 800-53 Rev. 5, Control SC-18

### In plain English

Define acceptable and unacceptable mobile code and mobile code technologies. In practice, this means you can prove you security management-level controls on a defined cadence.

## Why it matters

SP 800-53 is the catalogue every U.S. federal authorisation (FedRAMP, FISMA, CMMC) and most regulated industries point at. A missing control surfaces as a Plan of Action & Milestones (POA&M) item that an Authorizing Official must approve before the Authority To Operate is granted or renewed.

This control is rated **high**. Auditors expect a named owner, a remediation SLA, and a tooling artefact that evidences continuous operation.

## What an auditor looks for

A 3PAO (FedRAMP) or Independent Assessor (NIST RMF) tests against NIST SP 800-53A assessment procedures. For each control they expect a documented implementation that addresses every assessment objective (Examine, Interview, Test) and an implementation summary in the System Security Plan.

Within **System and Communications Protection**, the assessor will trace your implementation back to the catalogue reference (Control SC-18) and look for objective evidence on the latest two assessment cycles.

## How to implement

#### Secure Development

**Pipeline.** Require code review, SAST (Semgrep / Snyk Code), SCA (Dependabot / Renovate), secret-scanning and IaC scanning in the merge pipeline.

**Branch protection.** Protected branches enforce reviews, signed commits and passing CI before merge; document the protection rules as the control evidence.

#### Code Review Testing

**Pipeline.** Require at least one human reviewer plus passing CI (lint, type, unit, security scan) before merge — protected branches enforce this.

#### Endpoint Protection

**MDM.** Make MDM enrollment a hard gate for device access (Intune compliance + Conditional Access, or Jamf + Okta device trust). Unmanaged devices simply don't get a session token.

**EDR.** Deploy CrowdStrike / SentinelOne / Defender for Endpoint to every server and laptop; alert on any host that stops sending telemetry for >24h.

### Operational checklist

-   **Security.** Document the trigger, the owner and the cadence.
-   **Authorize.** Document the trigger, the owner and the cadence.
-   **Network.** Document the trigger, the owner and the cadence.
-   **Review.** Document the trigger, the owner and the cadence.
-   **Remote.** Document the trigger, the owner and the cadence.
-   **Scope:** management, system, application, protection, digital signatures, monitor, sources, review.

## Evidence to collect

-   **Code Repo Scan.** Source-control evidence — branch protection, required reviewers, CI status, SCA / SAST reports.

Source control pipelines (GitHub, GitLab) enforce SDLC guardrails. Focus: Mobile Code.

## Common pitfalls

-   CI security checks set to warn-only; the merge button is faster than the security feedback.
-   Pilot MDM rollouts that quietly exclude executives or engineers; carving out the highest-risk users is the most common audit failure.

## How it maps to other frameworks

Computed from shared tags, control component and key-operation subjects — handy when you are reconciling controls across an audit.

-   [**NIST SP 800-171 Rev. 3 3.13.13** — Mobile Code](https://support.icompaas.com/compliance/nist-sp-800-171-rev-3/3-13-13-mobile-code)

## Related controls in NIST SP 800-53 Rev. 5

-   [**Control SC-18(5)** — Allow Execution Only In Confined Environments](https://support.icompaas.com/compliance/nist-sp-800-53-rev-5/sc-18-5-allow-execution-only-in-confined-environments)
-   [**Control SC-7(9)** — Restrict Threatening Outgoing Communications Traffic](https://support.icompaas.com/compliance/nist-sp-800-53-rev-5/sc-7-9-restrict-threatening-outgoing-communications-traffic)
-   [**Control SI-7(6)** — Cryptographic Protection](https://support.icompaas.com/compliance/nist-sp-800-53-rev-5/si-7-6-cryptographic-protection)
-   [**Control SC-18(2)** — Acquisition, Development, And Use](https://support.icompaas.com/compliance/nist-sp-800-53-rev-5/sc-18-2-acquisition-development-and-use)
-   [**Control SC-26** — Decoys](https://support.icompaas.com/compliance/nist-sp-800-53-rev-5/sc-26-decoys)
-   [**Control SC-35** — External Malicious Code Identification](https://support.icompaas.com/compliance/nist-sp-800-53-rev-5/sc-35-external-malicious-code-identification)

## References

-   [NIST Computer Security Resource Center — NIST SP 800-53 Rev. 5](https://csrc.nist.gov/Projects/risk-management/sp800-53-controls)
-   Catalogue identifier: `Control SC-18`

Topics: governance riskapplication securitysecure developmentcode review testingdevsecopsendpoint protection

## Related compliance guidance

- [NIST SP 800-53 Rev. 5: a practical implementation guide for cloud teams](https://support.icompaas.com/compliance/nist-sp-800-53-rev-5): Start with the full NIST SP 800-53 implementation guide — scope, roadmap, evidence and how the assessment runs.
- [NIST SP 800-171 and CMMC: a practical guide to protecting CUI in the cloud](https://support.icompaas.com/compliance/nist-sp-800-171-rev-3): If your obligation is protecting CUI in your own systems for a federal or defence contract, this derived subset — not the full catalogue — is the requirement.
- [SOC 2 compliance: a practical implementation guide for cloud-native SaaS teams](https://support.icompaas.com/compliance/soc-2-trust-services-criteria): Most commercial SaaS already hold a SOC 2 Type 2, and FedRAMP 20x Class A is designed for providers that have one.
