03.03.08: Protection of Audit Information

To meet the 03.03.08: protection of audit information requirement, you must protect audit logs and related audit configuration from unauthorized access, modification, and deletion so audit records stay trustworthy for incident response and compliance assessment ¹. Operationalize this by restricting log access, hardening log pipelines, enforcing retention, and keeping repeatable evidence.

Key takeaways:

• Treat audit logs as high-value security data: protect confidentiality, integrity, and availability ¹.
• Implement access controls, tamper resistance, and controlled retention/disposal for audit information ¹.
• Keep assessment-ready evidence: configurations, access lists, retention settings, and change records tied to the system boundary.

Audit logs are your “system of record” for what happened, when it happened, and who did it. If audit information can be edited, deleted, or accessed by the wrong people, you lose the ability to investigate incidents credibly and to prove control operation during an assessment. Requirement 03.03.08: protection of audit information requirement in NIST SP 800-171 Rev. 3 pushes you to treat audit information like a protected asset, not a byproduct of IT operations ¹.

For a CCO or GRC lead, the fastest path to implementation is to translate “protect audit information” into a small set of enforceable control outcomes: (1) only authorized roles can access logs and audit settings, (2) logs cannot be quietly altered or purged, (3) logs are retained per defined rules, and (4) you can prove these facts with artifacts an assessor will accept. The work is cross-functional: security operations owns tooling and alerting, IT owns platform configuration, and compliance owns scoping, documentation, and evidence discipline.

This page gives you requirement-level guidance you can assign, track, and test.

Regulatory text

Requirement: “NIST SP 800-171 Rev. 3 requirement 03.03.08 (Protection of Audit Information).” ¹

Operator interpretation (what you must do): Protect audit information (audit logs, audit trails, and audit configurations) from unauthorized access and tampering so that audit data remains reliable for detection, investigation, and compliance validation ¹.

What “audit information” includes in practice (scope it explicitly):

• Security logs (SIEM events, EDR alerts, firewall logs, identity/authentication logs)
• System and application logs (OS event logs, database audit logs, SaaS admin activity logs)
• Audit configurations (what is logged, log levels, forwarding rules, retention policies)
• Log storage and transport components (log collectors, agents, pipelines, buckets, indices)

Plain-English requirement

You need to make sure audit logs and audit settings are protected like sensitive security evidence. Only the right people can view or manage them, and no one should be able to change or delete them without detection and proper authorization ¹. If an attacker compromises an admin account, your design should still make silent log tampering difficult and reviewable.

Who it applies to

Entity types

• Federal contractors and subcontractors
• Any nonfederal organization operating systems that handle Controlled Unclassified Information (CUI) ¹

Operational contexts where this becomes “real work”

• Hybrid environments where logs live across Windows/Linux, cloud platforms, and SaaS
• Shared administration models (IT admins with broad access, MSPs, or other third parties)
• DevOps pipelines where developers can deploy code that changes logging behavior
• Outsourced SOC/SIEM operations, where a third party needs log access but should not have unrestricted control

What you actually need to do (step-by-step)

Use the steps below as a build sheet. Each step should produce at least one artifact you can retain as evidence.

1) Define the system boundary and the “audit information” inventory

1. List in-scope systems that process, store, or transmit CUI.
2. For each system, identify:
   • Log sources (endpoints, servers, network devices, applications, cloud control plane, SaaS)
   • Log destinations (SIEM, log analytics, object storage, immutable storage)
   • Audit configuration owners (who can change what gets logged)
3. Document data flows for logs (source → collector/agent → transport → storage → SOC access).

Outcome: A scoping document that prevents “we thought Microsoft 365 was out of scope” surprises.

2) Establish role-based access control (RBAC) for log access and log administration

1. Create distinct roles:
   • Log readers (investigators, SOC analysts)
   • Log administrators (platform/SIEM engineers)
   • Audit policy owners (security governance)
2. Enforce least privilege:
   • Most users should read logs but not delete or reconfigure sources.
   • Limit who can disable logging, change retention, or modify forwarders.
3. Require strong authentication for privileged log access (for example, MFA through your identity provider), and avoid shared accounts.

Exam tip: Auditors often ask for the list of users/groups with log admin permissions and how it is reviewed.

3) Make logs tamper-resistant and deletion-controlled

1. Centralize logs where possible to reduce local tampering.
2. Restrict deletion:
   • Disable ad hoc delete privileges for most roles.
   • Require ticketed approval for purge actions (exception-only).
3. Protect integrity:
   • Enable integrity controls available in your logging platform (immutable storage options, write-once settings, or equivalent platform features).
   • Separate duties so the same person cannot both generate events and silently rewrite the log store.

Practical standard: If your logging tooling allows an administrator to delete evidence without generating an administrative audit trail, you have a control gap under 03.03.08 ¹.

4) Protect audit configurations (the “what gets logged” layer)

1. Baseline audit settings:
   • What events are collected (authentication, admin actions, policy changes, system changes)
   • Where logs are forwarded
   • Retention rules
2. Control changes:
   • Require change management for logging configuration modifications.
   • Record who approved and who implemented the change.
3. Monitor configuration drift:
   • Detect disabled log sources and broken forwarders.
   • Alert on changes to retention, ingestion filters, or parsing rules.

Common hangup: Teams protect log storage but forget that attackers can disable logging upstream. Treat audit configuration as audit information ¹.

5) Set retention and secure disposal rules (and apply them consistently)

1. Write a retention standard for audit logs tied to your risk and investigation needs.
2. Configure retention at every layer that stores logs (SIEM, cloud storage, endpoint log files, SaaS audit logs where available).
3. Document disposal controls for logs at end-of-life (secure deletion, controlled purge processes).

GRC note: NIST SP 800-171 Rev. 3 requires protection; it does not provide a single retention duration in the provided excerpt, so you must define and justify your retention standard based on contractual and operational needs ¹.

6) Operationalize evidence collection (assessment readiness)

1. Create an evidence map for 03.03.08:
   • Policy statement (what you require)
   • Technical implementation (how you do it)
   • Operating cadence (how you prove it stays true)
2. Set recurring checks:
   • Permissions review for log admin roles
   • Verification that key sources are still sending logs
   • Spot checks for retention settings and immutable storage controls

Where Daydream fits naturally: If you struggle to keep evidence current, Daydream can track the control-to-artifact mapping for 03.03.08, assign owners, and prompt recurring evidence pulls so your audit package is not rebuilt from scratch each cycle.

Required evidence and artifacts to retain

Keep evidence that proves design and operation, not just intent.

Policy and governance

• Logging and Monitoring Policy section stating audit information must be protected ¹
• Defined roles/responsibilities (SOC, IT, security governance)
• Change management procedure covering logging configuration changes

Technical configuration evidence

• Screenshots/exports showing:
  • SIEM/log platform RBAC roles and group memberships
  • Audit log storage settings (access controls, immutability options where enabled)
  • Retention settings for major log sources/destinations
• Sample administrative audit trail showing who changed logging settings (change events)

Operational evidence

• Access review records for log admin privileges (approvals, removals)
• Incident tickets demonstrating log access for investigations (read-only access where applicable)
• Monitoring/alert evidence for disabled log sources or pipeline failures
• Exception records for any needed purge/deletion activity (who approved, why, when)

Common exam/audit questions and hangups

Expect questions like:

1. “Who can delete logs?” Provide a definitive list and show it is restricted.
2. “Can an administrator alter logs without detection?” Explain integrity controls and admin activity logging.
3. “How do you protect logs from your own admins?” Show separation of duties, access review, and monitoring of admin actions.
4. “How do you know logging wasn’t disabled?” Show alerts for collector failures and configuration change tracking.
5. “What’s your retention policy, and where is it enforced?” Show the written standard and the platform settings that enforce it.

Frequent implementation mistakes (and how to avoid them)

Mistake	Why it fails 03.03.08	Fix
Treating logs as “IT data” with broad admin access	Unauthorized access/tampering risk is high 1	Create log-specific RBAC and restrict delete/config rights
Protecting SIEM storage but not log sources	Attackers disable logging upstream	Lock down audit configuration changes and monitor drift
No evidence package	Assessors can’t verify operation	Predefine artifacts and collect on a cadence
Shared accounts for SOC tools	No accountability, weak traceability	Use named accounts, MFA, and role-based permissions
Retention defined in policy but not implemented	Paper-only control	Enforce retention in each platform and retain proof

Enforcement context and risk implications

No public enforcement cases were provided in the source catalog for this requirement. Practically, failure of 03.03.08 increases the blast radius of any security incident: you may be unable to prove what data was accessed, determine root cause, or support required reporting and contractual obligations tied to CUI handling ¹. From an assessment standpoint, weak log protections also cast doubt on many other controls because audit trails are the validation mechanism.

A practical execution plan (30/60/90-day)

Use this as a sequencing tool. Adjust owners and depth based on your CUI boundary.

First 30 days (stabilize and scope)

• Define the CUI system boundary and log inventory for in-scope systems.
• Identify where logs are stored and who has admin rights today.
• Freeze uncontrolled changes: require tickets/approvals for log pipeline and retention changes.
• Draft the “Protection of Audit Information” control narrative tied to 03.03.08 ¹.

Days 31–60 (implement control guardrails)

• Implement RBAC clean-up: remove broad delete privileges and split reader vs admin roles.
• Enable available integrity/tamper-resistance features in your log storage/SIEM platform.
• Turn on administrative auditing for log platform actions and protect those admin logs as well.
• Establish recurring access reviews for log admin roles, with documented approvals.

Days 61–90 (operationalize and prove)

• Build an evidence pack: exports/screenshots, role lists, retention configs, sample change records.
• Test: run a tabletop scenario where you need to investigate an event and validate logs are complete and unaltered.
• Close gaps found in testing (missing sources, weak permissions, inconsistent retention).
• Put the control on a recurring compliance calendar in Daydream so evidence stays current.

Frequently Asked Questions

Does 03.03.08 require “immutable” (WORM) storage for logs?

The provided excerpt requires protection of audit information but does not prescribe a specific technology ¹. If immutability is available, it is a strong way to show tamper resistance, but you still need RBAC, admin auditing, and change control.

Are SaaS audit logs (like admin activity logs) in scope?

If the SaaS is part of your CUI system boundary or supports it, its audit logs and audit settings should be treated as audit information you protect ¹. Document how you access, retain, and restrict administrative control over those logs.

How do we handle a third-party SOC that needs access to our logs?

Give the third party a read-only role unless there is a documented need for administrative actions, then tightly scope and monitor those actions. Keep the contract/SOW and access approvals as part of your evidence package.

What evidence is most persuasive to an assessor for this requirement?

Platform-native exports that show roles, permissions, retention, and administrative audit trails are usually stronger than policy statements alone. Pair that with access review records and change tickets tied to logging configuration.

What if engineers need to change logging frequently during deployments?

Put logging configuration under change control that is compatible with DevOps (version control, peer review, and tracked approvals). The control goal is authorized, traceable change, not blocking safe change ¹.

How do we prove logs weren’t deleted during an incident?

Show deletion is restricted, show administrative actions are logged, and show retention controls that prevent ad hoc purge. During incidents, preserve relevant log sets through your incident response process and retain the preservation records.

Footnotes

1. NIST SP 800-171 Rev. 3