NIST SP 800-53 AU-9(3) Cryptographic Protection

Requirements NIST SOURCE

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

Discussion (NIST Supplemental 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.

Implementation Guidance

Engineering Interpretation

Original engineering commentary written for this explorer — not NIST source text and not authoritative guidance.

No engineering interpretation has been authored for AU-9(3) yet. This section is architected to receive it — see the Requirements and Assessment sections above for the authoritative NIST source content in the meantime.

Assessment

NIST SP 800-53A REV 5.2.0

Assessment Objectives

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

Examine

[SELECT FROM: Audit and accountability policy; system security plan; privacy plan; access control policy and procedures; procedures addressing protection of audit information; system design documentation; system hardware settings; system configuration settings and associated documentation; system audit records; other relevant documents or records].

Interview

[SELECT FROM: Organizational personnel with audit and accountability responsibilities; organizational personnel with information security and privacy responsibilities; system/network administrators; system developers].

Test

[SELECT FROM: Cryptographic mechanisms protecting the integrity of audit information and tools].

Overlays

Showing the OT/ICS overlay for the parent control AU-9 — see the AU-9(3) entries within each baseline below.

OT/ICS Overlay SP 800-82r3

NIST SP 800-82r3 Appendix F, Table 22. Blank baseline means the control/control enhancement is not selected in that initial OT baseline.

LOW

Base control: Included (matches standard baseline)

MODERATE

Base control: Included (matches standard baseline)
Included: (4)

HIGH

Base control: Included (matches standard baseline)
Included: (2) (3) (4)

STIGs & CCIs

No STIG checks or CCI mappings are currently loaded for AU-9(3). This section is architected to display, per product: STIG ID, Finding ID, Severity, Title, Description, Check, Fix, CCI, and NIST control mapping — but nothing is populated here until a real DISA STIG/CCI dataset is ingested.

Learn more about STIG/CCI integration →

Evidence

Potential Evidence — Derived

Categorized from the SP 800-53A "Examine"/"Test" artifact list above by keyword — not an authoritative NIST evidence list.

Policy

Audit and accountability policy
system security plan
privacy plan
access control policy and procedures

Configuration

system design documentation
system configuration settings and associated documentation

Testing

Cryptographic mechanisms protecting the integrity of audit information and tools

Other Records

procedures addressing protection of audit information
system hardware settings
system audit records
other relevant documents or records