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SC-18_mobile-code

DevOps & Security
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Define acceptable and unacceptable mobile code and mobile code technologies;

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How to use this skill

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  2. Copy the prompt below and paste it into your agent.
  3. Review the proposed files and risks before you approve installation.
Prompt to paste
I want to install this Agent Skill for this project in Codex.

Source SKILL.md: https://github.com/CyberStrikeus/CyberStrike/blob/HEAD/.cyberstrike/skill/NIST/SP800-53_rev5/SC_system-and-communications-protection/SC-18_mobile-code/SKILL.md

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First, summarize what it does, its dependencies, license status if identifiable, and any risks. Show the exact files you propose to add under .agents/skills/sc-18-mobile-code/. Do not write files or run scripts until I approve.

After I approve, install the complete skill folder, including required referenced files, into that project location. Verify it is discoverable, then tell me its actual invocation name and how to use it. Do not claim it is installed until you have verified it.

Copying this prompt does not install or run the skill. Review third-party files before use. Codex skill guide

SC-18 Mobile Code

High-Level Description

Family: System and Communications Protection (SC) Framework: NIST SP 800-53 Rev 5

Mobile code includes any program, application, or content that can be transmitted across a network (e.g., embedded in an email, document, or website) and executed on a remote system. Decisions regarding the use of mobile code within organizational systems are based on the potential for the code to cause damage to the systems if used maliciously. Mobile code technologies include Java applets, JavaScript, HTML5, WebGL, and VBScript. Usage restrictions and implementation guidelines apply to both the selection and use of mobile code installed on servers and mobile code downloaded and executed on individual workstations and devices, including notebook computers and smart phones. Mobile code policy and procedures address specific actions taken to prevent the development, acquisition, and introduction of unacceptable mobile code within organizational systems, including requiring mobile code to be digitally signed by a trusted source.

What to Check

  • Verify SC-18 Mobile Code is documented in SSP
  • Validate all 2 control requirements are implemented
  • Confirm control is operating effectively
  • Review evidence of continuous monitoring for SC-18

How to Test

Step 1: Review Documentation

Examine the System Security Plan (SSP) and related artifacts for SC-18 implementation details. Verify the organization has documented how this control is satisfied.

Step 2: Validate Implementation

# For cloud environments, use cloud-audit-mcp tools
# For on-premises, review system configurations directly

# Example: Check if account management policies exist
grep -r "account.management\|access.control" /etc/security/ 2>/dev/null

Step 3: Test Operating Effectiveness

Verify the control is actively functioning, not just documented. Check logs, configurations, and operational evidence.

Tools

ToolPurposeUsage
cloud-audit-mcpCheck encryption and network controlscloud_audit_encryption
nmapNetwork scanningnmap -sV --script ssl-enum-ciphers

Remediation Guide

Control Statement

Define acceptable and unacceptable mobile code and mobile code technologies; and Authorize, monitor, and control the use of mobile code within the system.

Implementation Guidance

Mobile code includes any program, application, or content that can be transmitted across a network (e.g., embedded in an email, document, or website) and executed on a remote system. Decisions regarding the use of mobile code within organizational systems are based on the potential for the code to cause damage to the systems if used maliciously. Mobile code technologies include Java applets, JavaScript, HTML5, WebGL, and VBScript. Usage restrictions and implementation guidelines apply to both the selection and use of mobile code installed on servers and mobile code downloaded and executed on individual workstations and devices, including notebook computers and smart phones. Mobile code policy and procedures address specific actions taken to prevent the development, acquisition, and introduction of unacceptable mobile code within organizational systems, including requiring mobile code to be digitally signed by a trusted source.

Risk Assessment

FindingSeverityImpact
SC-18 Mobile Code not implementedHighSystem and Communications Protection
SC-18 partially implementedMediumIncomplete System and Communications Protection

CWE Categories

CWE IDTitle
CWE-311Missing Encryption of Sensitive Data

References

Checklist

  • Control documented in SSP
  • Implementation evidence collected
  • Operating effectiveness validated
  • Continuous monitoring in place
  • Related controls (AU-2, AU-12, CM-2, CM-6, SI-3) reviewed