Audit and Accountability 3.3.1 (3.3.1)
Create and retain system audit logs and records to the extent needed to enable the monitoring, analysis, investigation, and reporting of unlawful or unauthorized system activity
Get Full GuidanceWhat Is This CMMC Control?
This control requires organizations to create and keep audit logs that record security-relevant events in their systems. These logs must capture enough detail to detect, investigate, and report unauthorized or unlawful activities. Organizations must decide which events to log based on their security needs, balancing thoroughness with system performance. Logs should include key information like timestamps, user identifiers, event descriptions, and success/failure indicators. The goal is to maintain sufficient records to support security monitoring, incident investigation, and compliance reporting without overwhelming systems or analysts with unnecessary data.
Control Intent
To ensure organizations maintain sufficient audit records to detect, investigate, and respond to security incidents and unauthorized system activity involving CUI.
Who This Control Applies To
- •All systems that process, store, or transmit CUI
- •Network devices that control access to CUI systems
- •Security tools and applications that protect CUI
- •Authentication systems and identity management platforms
- •Database systems containing CUI
- •File servers and storage systems with CUI
- •Cloud services and SaaS applications handling CUI
- •Endpoints and workstations accessing CUI
- •Virtual infrastructure hosting CUI workloads
Not Applicable When
- •Systems that never process, store, or transmit CUI
- •Standalone systems with no network connectivity and no CUI access
- •Systems explicitly scoped out of the CUI environment
- •Air-gapped systems not part of the assessment boundary
Key Objectives
- 1Enable detection of unauthorized or unlawful system activity through comprehensive audit logging
- 2Provide sufficient audit record detail to support security investigations and incident response
- 3Maintain audit logs that facilitate monitoring and analysis of security-relevant events
- 4Support compliance reporting and forensic analysis through retained audit records
Sample Self-Assessment Questions (Partial)
Does your organization currently collect audit logs from systems that handle CUI?
What types of events are currently being logged in your CUI systems (e.g., login attempts, file access, configuration changes)?
Implementation Approaches (High-Level)
Centralized SIEM with Comprehensive Event Collection
Deploy a Security Information and Event Management (SIEM) system that collects, aggregates, and retains audit logs from all in-scope systems including servers, network devices, endpoints, and cloud services.
Native Cloud Platform Audit Logging
Utilize native audit logging capabilities provided by cloud service providers (AWS CloudTrail, Azure Monitor, GCP Cloud Audit Logs) with appropriate retention and centralization.
Per-System Local Logging with Centralized Collection
Configure audit logging on individual systems using native operating system and application capabilities, with logs forwarded to a centralized collection point for retention and analysis.
Managed Security Service Provider (MSSP) Log Management
Engage a managed security service provider to collect, retain, and analyze audit logs from in-scope systems on behalf of the organization.
Hybrid On-Premises and Cloud Log Aggregation
Implement a hybrid logging architecture that aggregates logs from both on-premises systems and cloud services into a unified retention and analysis platform.
Evidence & Assessment Notes
Expected Evidence
Organizations should maintain documentation and evidence demonstrating compliance with this control. This may include policy documentation, configuration records, audit logs, access reviews, and other relevant artifacts that show how the control is implemented and maintained.
Plan of Action & Milestones (POA&M)
If audit logging is not enabled on all in-scope systems, create a POA&M with milestones for enabling logging on each system type, prioritizing systems with highest CUI exposure If retention periods are insufficient, document current retention capability and create milestones for implementing storage expansion or archival solutions If centralized log collection is not implemented, create a phased POA&M starting with critical systems and expanding to full scope If specific event types are not being logged, document the gap and create milestones for configuring required event logging If cloud services lack audit logging integration, create milestones for enabling native cloud logging and integrating with centralized collection If audit logs are not protected from tampering, create milestones for implementing access controls and log integrity mechanisms For performance-related logging limitations, document the risk acceptance process and create milestones for implementing solutions that balance logging and performance If SIEM or log management platform is needed but not yet procured, create milestones for vendor selection, procurement, deployment, and configuration Include specific completion criteria in POA&M milestones such as percentage of systems with logging enabled, retention period achieved, or event types configured Ensure POA&M includes verification activities to confirm logging is functioning as intended after implementation
Frequently Asked Questions
What specific events must be logged to satisfy this control?
The control does not prescribe specific events but requires organizations to determine event types based on their security needs. Common events include authentication attempts (successful and failed), privilege escalation, access to CUI, configuration changes, and administrative actions. Organizations should consider what events are necessary to detect unauthorized CUI access and support incident investigation.
How long must audit logs be retained?
The control requires retention to the extent needed for monitoring, analysis, investigation, and reporting. While no specific period is mandated, organizations typically retain logs for 90 days to one year based on their risk assessment, regulatory requirements, and incident response needs. The retention period must be documented and consistently applied.
Do we need to log every single event on every system?
No. Organizations must balance logging comprehensiveness with system performance and analysis capability. The control allows organizations to determine which events are significant and relevant to CUI security. However, systems must have the capability to log required events even if that capability is not always activated due to performance concerns.
Can we use cloud provider native logging to satisfy this control?
Yes. Native cloud platform audit logging (AWS CloudTrail, Azure Monitor, GCP Cloud Audit Logs) can satisfy this control if properly configured with adequate retention and the logs capture required security events. Organizations must ensure cloud logs are retained for the required period and are accessible for review and analysis.
What happens if we cannot implement full audit logging immediately?
Organizations can document gaps in a Plan of Action and Milestones (POA&M) with specific milestones for achieving full compliance. The POA&M should prioritize systems with highest CUI exposure and include concrete steps for enabling logging, implementing retention, and establishing centralized collection. Assessors will evaluate the adequacy and progress of the POA&M.
How do we prove that audit logging is working correctly during an assessment?
Assessors will request sample audit logs from representative systems, review logging configurations, verify retention periods, and confirm that required event types are being captured. Organizations should be prepared to demonstrate log collection status, provide sample logs showing required data elements, and show evidence of regular log review activities.
How ConformatIQ Helps With CMMC Readiness
ConformatIQ is an AI-assisted CMMC readiness platform designed to help organizations prepare for assessments more efficiently. The platform supports document generation such as SSPs and POA&Ms, guided readiness workflows, centralized evidence tracking, and interview preparation for assessments.
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Request Full GuidanceInformation sourced from NIST SP 800-171 Rev. 2. See full disclaimer.