AU.L2-3.3.5  

Reference: CMMC v2.13

Family: AU

Level Introduced: 2

Title: Audit Correlation

Practice:
Correlate audit record review, analysis, and reporting processes for investigation and response to indications of unlawful, unauthorized, suspicious, or unusual activity.

Further Discussion:
Companies must review, analyze, and report audit records to help detect and respond to security incidents in a timely manner for the purpose of investigation and corrective actions. Collection of audit logs into one or more central repositories may facilitate correlated review. Small companies may be able to accomplish this manually with well-defined and -managed procedures. Larger companies will use an automated system for analysis that correlates log data from across the entire enterprise. Some companies may want to orchestrate the analysis process to include the use of Application Programming Interfaces (APIs) for collection, correlation, and the automation of responses based on programed rulesets.

Example
You are a member of a cyber defense team responsible for audit log analysis. You run an automated tool that analyzes all the audit logs across a Local Area Network (LAN) segment simultaneously looking for similar anomalies on separate systems at separate locations. Some of these systems store CUI. After extracting anomalous information and performing a correlation analysis [b], you determine that four different systems have had their event log information cleared between 2:00 AM to 3:00 AM, although the associated dates are different. The team monitors all systems on the same LAN segment between 2:00 AM to 3:00 AM for the next 30 days.

Potential Assessment Considerations
• Are mechanisms used across different repositories to integrate audit review, analysis, correlation, and reporting processes [b]?

Source: CMMC v2.13