System Use Notification (03.01.09)_system-use-notification

DevOps & Security

System Use Notification

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Source SKILL.md: https://github.com/CyberStrikeus/CyberStrike/blob/HEAD/.cyberstrike/skill/NIST/SP800-171_rev3/03.01_access-control/System%20Use%20Notification%20(03.01.09)_system-use-notification/SKILL.md

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System Use Notification (03.01.09) System Use Notification

High-Level Description

Family: Access Control Framework: NIST SP 800-171 Rev 3 Applicability: Systems processing, storing, or transmitting CUI

System Use Notification

What to Check

Verify System Use Notification (03.01.09) System Use Notification is implemented for CUI systems
Review SSP documentation for System Use Notification (03.01.09)
Validate CMMC Level 2 assessment objective for System Use Notification (03.01.09)
Confirm POA&M addresses any gaps for System Use Notification (03.01.09)

How to Test

Step 1: Review System Security Plan

Examine the SSP for System Use Notification (03.01.09) implementation description and responsible parties.

Step 2: Assess Implementation

# Verify security controls protecting CUI
# Check access controls, encryption, monitoring as applicable

# For Linux systems:
ls -la /etc/security/ 2>/dev/null
grep -r "CUI\|controlled" /etc/security/ 2>/dev/null

# For cloud:
# Use cloud-audit-mcp tools to assess posture

Step 3: CMMC Assessment Validation

Verify this requirement passes CMMC Level 2 assessment methodology per SP 800-171A Rev 3.

Tools

Tool	Purpose	Usage
cloud-audit-mcp	Assess cloud CUI environment	`cloud_audit_*` tools
Manual Review	SSP and POA&M review	Documentation analysis

Remediation Guide

Requirement Statement

Implement System Use Notification per NIST SP 800-171 Rev 3.

Supplemental Guidance

System use notifications can be implemented using messages or warning banners. The messages or warning banners are displayed before individuals log in to a system that processes, stores, or transmits CUI. System use notifications are used for access via logon interfaces with human users and are not required when human interfaces do not exist. Organizations consider whether a secondary use notification is needed to access applications or other system resources after the initial network logon. Posters or other printed materials may be used in lieu of an automated system message. This requirement is related to 03.15.03.

Risk Assessment

Finding	Severity	Impact
System Use Notification (03.01.09) System Use Notification not implemented	High	CUI Protection - Access Control
System Use Notification (03.01.09) partially implemented (POA&M)	Medium	CMMC certification risk

CWE Categories

CWE ID	Title
CWE-284	Improper Access Control

References

Checklist

SSP documents System Use Notification (03.01.09) implementation
Evidence of operating effectiveness collected
POA&M addresses any gaps
CMMC assessment objective met
Continuous monitoring active