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AU.2.042
Content
Control Acronym
AU
Family
Audit And Accountability
CMMC Level
2
800-171 Control #
3.3.1
CMMC Description
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.
CMMC Clarification
You should ensure that the system creates and retains audit logs. The logs should contain enough information to identify and investigate unlawful or unauthorized system activity. You select the events that require auditing. Also, you determine the information to record in the audit logs about those events. Example You set up audit logging capability for your organization. You determine that all systems that contain CUI must have extra detail in the audit logs. Because of this, you configure these systems to log the following information for all user actions: * time stamps * source and destination addresses * user or process identifiers * event descriptions * success or fail indications * filenames.
800-171 Description
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.
800-171 Discussion
An event is any observable occurrence in a system, which includes unlawful or unauthorized system activity. Organizations identify event types for which a logging functionality is needed as those events which are significant and relevant to the security of systems and the environments in which those systems operate to meet specific and ongoing auditing needs. Event types can include password changes, failed logons or failed accesses related to systems, administrative privilege usage, or third-party credential usage. In determining event types that require logging, organizations consider the monitoring and auditing appropriate for each of the CUI security requirements. Monitoring and auditing requirements can be balanced with other system needs. For example, organizations may determine that systems must have the capability to log every file access both successful and unsuccessful, but not activate that capability except for specific circumstances due to the potential burden on system performance. Audit records can be generated at various levels of abstraction, including at the packet level as information traverses the network. Selecting the appropriate level of abstraction is a critical aspect of an audit logging capability and can facilitate the identification of root causes to problems. Organizations consider in the definition of event types, the logging necessary to cover related events such as the steps in distributed, transaction-based processes (e.g., processes that are distributed across multiple organizations) and actions that occur in service-oriented or cloud- based architectures. Audit record content that may be necessary to satisfy this requirement includes time stamps, source and destination addresses, user or process identifiers, event descriptions, success or fail indications, filenames involved, and access control or flow control rules invoked. Event outcomes can include indicators of event success or failure and event-specific results (e.g., the security state of the system after the event occurred). Detailed information that organizations may consider in audit records includes full text recording of privileged commands or the individual identities of group account users. Organizations consider limiting the additional audit log information to only that information explicitly needed for specific audit requirements. This facilitates the use of audit trails and audit logs by not including information that could potentially be misleading or could make it more difficult to locate information of interest. Audit logs are reviewed and analyzed as often as needed to provide important information to organizations to facilitate risk-based decision making. [SP 800-92] provides guidance on security log management.
Other Source Discussion
N/A
CIS Control References
CIS Controls v7.1 6.2
NIST 800-53 Control Ref.
NIST SP 800-53 Rev 4 AU-2, AU-3, AU-3(1), AU-6, AU-11, AU-12
CMMC Derived
NIST CSF Control References
NIST 800-171 References
NIST SP 800-171 Rev 1 3.3.1
Applicable FAR Clause
NIST CSF Control Reference
NIST CSF v1.1. DE.CM-1, DE.CM-3, DE.CM-7
CERT RMM Reference
CERT RMM v1.2 MON:SG2.SP3
Modification of NIST 800-171B Reference
NIST 800-171B Reference
UK NCSCCyber Reference
AS ACSC Reference
Sub-Criterias
Assessment Sub-Criteria 1
AU.2.042.[a] audit logs needed (i.e., event types to be logged) to enable the monitoring, analysis, investigation, and reporting of unlawful or unauthorized system activity are specified;
Assessment Sub-Criteria 2
AU.2.042.[b] the content of audit records needed to support monitoring, analysis, investigation, and reporting of unlawful or unauthorized system activity is defined;
Assessment Sub-Criteria 3
AU.2.042.[c] audit records are created (generated);
Assessment Sub-Criteria 4
AU.2.042.[d] audit records, once created, contain the defined content;
Assessment Sub-Criteria 5
AU.2.042.[e] retention requirements for audit records are defined; and
Assessment Sub-Criteria 6
AU.2.042.[f] audit records are retained as defined.