AU-9(3)_cryptographic-protection

AU-9(3) Cryptographic Protection

Enhancement of: AU-9

High-Level Description

Family: Audit and Accountability (AU) Framework: NIST SP 800-53 Rev 5

Cryptographic mechanisms used for protecting the integrity of audit information include signed hash functions using asymmetric cryptography. This enables the distribution of the public key to verify the hash information while maintaining the confidentiality of the secret key used to generate the hash.

What to Check

• Verify AU-9(3) Cryptographic Protection is documented in SSP
• Confirm control is operating effectively
• Review evidence of continuous monitoring for AU-9(3)
• Verify enhancement builds upon base control AU-9

How to Test

Step 1: Review Documentation

Examine the System Security Plan (SSP) and related artifacts for AU-9(3) 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

Remediation Guide

Control Statement

Implement cryptographic mechanisms to protect the integrity of audit information and audit tools.

Implementation Guidance

Cryptographic mechanisms used for protecting the integrity of audit information include signed hash functions using asymmetric cryptography. This enables the distribution of the public key to verify the hash information while maintaining the confidentiality of the secret key used to generate the hash.

Risk Assessment

CWE Categories

References

• NIST SP 800-53 Rev 5 - AU-9(3)
• NIST SP 800-53A Rev 5 (Assessment Procedures)
• NIST SP 800-53 Rev 5 Full Catalog

Checklist

• Control documented in SSP
• Implementation evidence collected
• Operating effectiveness validated
• Continuous monitoring in place
• Related controls (AU-10, SC-12, SC-13) reviewed