Security requirement
- a.Specify the following event types selected for logging within the system: [Organization-defined: event types].
- b.Review and update the event types selected for logging [Organization-defined: frequency].
Discussion
An event is any observable occurrence in a system, including unlawful or unauthorized system activity. Organizations identify event types for which a logging functionality is needed. This includes events that are 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, the execution of privileged functions, failed logons or accesses related to systems, administrative privilege usage, or third-party credential usage. In determining event types that require logging, organizations consider the system monitoring and auditing that are appropriate for each of the security requirements. When defining event types, organizations consider 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. 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 only activate that capability under specific circumstances due to the potential burden on system performance. The event types that are logged by organizations may change over time. Reviewing and updating the set of logged event types are necessary to ensure that the current set of event types remains relevant.
Tailoring decisions required
Resolve these values through the governing organization’s approved tailoring and risk-management process before declaring the requirement implemented.
Implementation perspective
Treat Event Logging as a CUI protection outcome that must be reflected in the system boundary, documented implementation, operational behavior, and assessment evidence. Pay particular attention to event selection, trustworthy logging, review, retention, and support for CUI investigations.
- Confirm the requirement is in scope for the CUI system components, services, users, and external connections being assessed.
- Resolve every organization-defined parameter through an approved governance and tailoring process.
- Map each clause of the requirement to an accountable owner, implementation mechanism, and evidence source.
- Verify that inherited and shared implementations are supported by current provider evidence and responsibility boundaries.
- Collect evidence during normal operation and review changes, exceptions, and deficiencies on a risk-based cadence.
Questions to ask
- Which CUI assets, data flows, users, and services are protected by this requirement?
- Which portions are implemented locally, inherited, shared, or not applicable, and what evidence supports that determination?
- Do the system security plan, deployed configuration, operating process, and assessment evidence tell the same story?
- What change, incident, or threshold should trigger reassessment?
Evidence and validation
- logging standards and event-selection decisions
- sample audit records and retention settings
- time synchronization evidence
- alert review and investigation records
Common failure patterns
- collecting logs without defined use cases
- critical CUI events absent from the audit trail
- retention shorter than investigative needs
- logs modifiable by the same administrators being monitored
Assessment objectives and methods
Assessment objectives (3)
- a.
the following event types are specified for logging within the system: [Organization-defined: event types].
- b.
the event types selected for logging are reviewed [Organization-defined: frequency].
- b.
the event types selected for logging are updated [Organization-defined: frequency].
Examine
- audit and accountability policy and procedures
- procedures for auditable events
- system design documentation
- system configuration settings
- system audit records
- system auditable events
- system security plan
- other relevant documents or records
Interview
- personnel with audit and accountability responsibilities
- personnel with information security responsibilities
- system administrators
Test
- mechanisms for implementing system auditing
Source NIST SP 800-53 controls
These controls are referenced by the official SP 800-171 Rev. 3 OSCAL record. Open the corresponding control pages for complete control text, enhancements, D3FEND mappings, and related learning.
Authoritative sources
- NIST SP 800-171 Revision 3 official publication ↗
- NIST SP 800-171A Revision 3 official publication ↗
- NIST OSCAL Content release used for this import ↗
Bare Metal Cyber is an independent educational publisher and is not affiliated with or endorsed by NIST. The official publications, the responsible federal agency, and the governing contract or agreement determine applicability, tailoring, assessment depth, and required implementation.