Domain: Information
Question:
A financial services company is migrating sensitive banking and identity workloads into AWS and is trying to level up both fraud detection and cloud security. After a major account takeover campaign, investigators realized key signals are scattered across different logging tools. Authentication events, device fingerprinting, transaction risk signals, and fraud alerts all live in separate places. That fragmentation is slowing down investigations, stretching time to containment, making regulatory reporting harder, and weakening the company's ability to support chargebacks or respond to law enforcement requests. Using the NIST 800-53 controls referenced in your mapping, especially the Audit and Accountability and System and Information Integrity families (AU-2, AU-6, AU-9, and SI-4), what should a centralized logging setup look like so it is tamper-resistant and actually usable for fraud and security teams? And where does CP-9 fit in if the goal is to preserve evidence long term for disputes and forensics?

Expected points in a correct answer:
Identifies that the described problems violate AU-2b (the necessity to enhance and support auditable events) and AU-2c (the justification for why audited events are adequate).
Recommends establishing a unified logging strategy guided by AU-2 (Event Logging) to address fragmented telemetry across platforms following security incidents.
Specifies that authentication events must be consistently captured across all platforms as part of the unified logging strategy.
Specifies that device fingerprint changes must be consistently captured across all platforms as part of the unified logging strategy.
Specifies that high-risk transactions must be consistently captured across all platforms as part of the unified logging strategy.
Specifies that fraud alerts must be consistently captured across all platforms as part of the unified logging strategy.
Specifies that investigative actions must be consistently captured across all platforms as part of the unified logging strategy.
States that the unified logging strategy aids in creating a baseline dataset that supports reliable attribution and regulatory reporting.
States that AU-3 requires the source, outcome, and identity each to be documented for every security event.
Recommends implementing AWS CloudTrail as the primary mechanism for capturing event logs within the unified logging architecture.
Recommends implementing S3 bucket logging in conjunction with CloudTrail as a log storage component of the unified logging architecture.
States that CloudTrail configured to report access and assignment events satisfies many aspects of AU-5 (Response to Audit Logging Process Failures).
Recommends configuring alerts using AWS CloudWatch or third-party solutions integrated with the AWS environment to supplement CloudTrail logging.
States that CloudTrail logs can be parsed and alerted upon when users connect from unexpected locations or malicious IP addresses to satisfy SI-4 (System Monitoring) and support detection of suspicious authentication patterns.
States that AU-9 (Protection of Audit Information) requires logs to be tamper-resistant, access-controlled, and preserved in write-once or immutable storage to protect evidentiary integrity.
Recommends storing logs in S3 buckets with server-side encryption enabled by default as an AU-9 implementation measure.
Recommends offloading logs to a SIEM platform for enhanced detection capability and long-term log retention as a complement to S3 bucket storage.
States that a SIEM platform enables centralized ingestion of logs from all log sources across the environment beyond what CloudTrail alone captures.
Recommends locking down all logging configurations with AWS IAM groups and roles to prevent unauthorized modification or deletion of audit logs.
Recommends applying CP-9 (System Backup) to ensure long-term preservation of fraud evidence that may be needed after the original fraud event has occurred.
States that CP-9-compliant backup retention supports chargeback disputes, customer remediation cases, regulatory audits, and law-enforcement inquiries.
Recommends that backup configurations include rollback capabilities that are tested against relevant industry compliance frameworks.
States that organizations should define both backup frequency and rollback testing cadence as part of their CP-9 implementation planning.
Recommends standardizing log formats across all platforms to enable consistent cross-platform event correlation during forensic investigations.
Recommends defining log retention periods aligned with applicable regulatory and legal requirements to ensure audit evidence remains available when needed.
Recommends implementing log integrity verification mechanisms such as cryptographic hashing to detect unauthorized tampering of stored audit records.
Recommends conducting periodic access reviews of IAM permissions governing log storage and configuration to detect and remediate permission drift over time.
Recommends tuning SI-4 detection rules over time to reduce false positives in alerts generated by unexpected location and malicious IP address patterns.
Recommends establishing documented chain-of-custody procedures for audit logs submitted in support of law-enforcement inquiries or legal proceedings.
Recommends integrating CloudTrail and SIEM alert triggers into an incident response playbook to ensure consistent and repeatable response to detected anomalies.
Recommends validating SIEM detection rule fidelity against simulated fraud event scenarios before deploying detection rules to production environments.
Recommends documenting the mapping between implemented audit logging controls and their corresponding NIST SP 800-53 Rev. 5 control identifiers to support assessment and audit readiness.
Maintains written governance program documentation covering scope, policies, role definitions, and review procedures to ensure repeatability and auditability of the access control program.
Configures automated alerts triggered by any detected privilege escalation attempt by human or non-human identities across the AWS environment.
States that event logs in a mature program are critical, requiring dedicated retention and backup strategies.