Case Study: Fast-Growing UK Fintech Passes Critical Audit with Amazon Security Lake

AWS Security Competency Case Study: Threat Detection and Response

A fast-growing UK-based fintech organisation successfully passed a critical security audit by implementing Amazon Security Lake, achieving immediate compliance whilst establishing a modern, cost-effective security monitoring capability. HOOP Cyber delivered the complete solution from proof-of-concept to production in just 4 weeks, enabling the client to meet stringent audit requirements and demonstrate comprehensive security logging and threat detection.

Challenges

The fintech operates a cloud-native digital platform handling sensitive financial transactions and customer data. Following a recent audit, they were mandated to implement a comprehensive security monitoring system to demonstrate adequate security logging and threat detection capabilities.

Key Challenges:

• Audit Compliance Deadline: Immediate requirement to implement security monitoring to pass regulatory audit
• No Existing Security Lake: Lack of centralised security event logging across AWS infrastructure
• Multi-Source Integration: Need to ingest both AWS-native and third-party security data sources
• Cost Constraints: Traditional SIEM solutions were cost and performance prohibitive for the required data volume and retention
• Cloud-Native Requirements: As a digital-first organisation, needed a solution that aligned with modern cloud architecture
• Time Pressure: Limited timeframe to design, deploy, and demonstrate operational capability
• Data Normalisation: Required consistent format for querying across diverse log sources

Business Impact: Without a compliant security monitoring solution, the organisation faced potential regulatory sanctions, inability to operate in regulated markets, reputational damage, and increased risk of undetected security incidents affecting customer financial data.

Solutions

HOOP Cyber implemented a cloud-native security operations architecture based on Amazon Security Lake, delivering immediate audit compliance with a modern threat detection capability that provides long-term scalability and cost efficiency.

Core Architecture:

• Amazon Security Lake: Centralised security data repository with native OCSF normalisation, providing compressed Parquet format storage for cost-effective long-term retention
• Multi-Source Data Integration: Native AWS log sources (CloudTrail, S3 Data Events, WAF, VPC Flow) with seamless ingestion
• Third-Party Integration via Firehose: Custom OCSF normalisation for external sources including Okta, Jamf, and GitHub
• Amazon Athena Query Interface: SQL-based security investigations across normalised data with five pre-defined threat hunting queries
• Dual Storage Strategy: Security Lake for normalised, queryable data alongside full-fidelity S3 archives for compliance
• OCSF Framework: Open Cybersecurity Schema Framework ensuring consistent queries across all current and future data sources

Key AWS Services Deployed:

Amazon Security Lake, Amazon Athena, Amazon Kinesis Data Firehose, AWS CloudTrail, Amazon S3 with Intelligent-Tiering, AWS Lambda, AWS Glue Data Catalogue, AWS IAM, Amazon VPC Flow Logs, AWS WAF

Implementation Approach:

• Week 1-2: Architecture design, Security Lake instantiation, automated AWS log source ingestion (CloudTrail, S3, WAF, VPC Flow), infrastructure validation
• Week 3: HOOP Cyber supported third-party data source integration (Okta, Jamf, GitHub) via Firehose, custom OCSF normalisation development, data quality validation
• Week 4: Athena query development for five key security use cases, detection query templates, audit documentation preparation, security team enablement
• Post-Implementation: Production deployment, formal audit demonstration, compliance documentation, roadmap for future enhancements

Operational Use Cases Delivered:

1. Regular review of priority incident alerts (scheduled every 5 minutes)
2. Investigating suspicious user activity
3. Hunting for malware and intrusions
4. Detecting insider threats
5. Advanced threat hunting

Why This Architecture:

• Audit-Ready from Day One: Immediate operational capability meeting regulatory requirements
• Cost-Effective Compliance: Storage compression exceeding 90% reduces long-term costs versus traditional SIEM
• OCSF Standardisation: Unified query language across AWS and third-party sources simplifies investigations
• Scalable Foundation: Cloud-native architecture grows with business without proportional cost increases
• No Infrastructure Overhead: Serverless components eliminate operational management burden
• Flexible Integration: Firehose-based ingestion enables rapid addition of new data sources
• Industry Best Practice: Leverages AWS security competency expertise from enterprise deployments

Results

The implementation delivered immediate audit compliance whilst establishing a modern security operations foundation that positions the fintech for continued growth and security maturation.

Quantified Business Outcomes

• Audit Success: Passed critical security audit demonstrating comprehensive logging and threat detection
• 4-Week Deployment: Complete proof-of-concept to production deployment meeting tight audit deadline
• 90%+ Storage Efficiency: Data compression through Parquet and GZIP formats dramatically reducing storage costs
• Multi-Year Retention: Cost-effective long-term data retention supporting regulatory requirements
• Multi-Source Integration: Successfully ingested 7 critical log sources (4 AWS-native, 3 third-party)
• Immediate Querying: Five operational threat hunting queries ready for daily security operations
• Compliance Documentation: Complete audit trail demonstrating security monitoring capabilities
• Cost Avoidance: Eliminated need for expensive traditional SIEM whilst exceeding functional requirements

Security Capabilities Delivered

• Comprehensive Visibility: Unified view across AWS infrastructure, identity systems (Okta), endpoint management (Jamf), and code repositories (GitHub)
• Pre-Built Detection Queries: Five threat hunting templates mapped to key security use cases including insider threats and malware detection
• Standardised Investigation: OCSF normalisation enables consistent queries across all data sources
• Automated Alerting Framework: Scheduled queries detecting priority incidents every 5 minutes
• Self-Service Analytics: Security team independence with Athena SQL interface requiring no specialist tools
• Dual-Purpose Storage: Normalised data for investigations alongside full-fidelity archives for compliance
• Scalable Data Ingestion: Proven architecture supporting future integration of additional security tools

Final Thoughts

This solution enabled the fintech to pass their critical audit whilst establishing a modern, cloud-native security operations capability that supports continued regulatory compliance and business growth. The flexible OCSF-based architecture provides a future-proof foundation for additional data sources and advanced security analytics capabilities.

The implementation demonstrates that organisations can achieve regulatory compliance without the cost and complexity of legacy SIEM platforms, whilst gaining superior scalability and analytical capabilities through cloud-native AWS services. Most critically, the fintech transformed an urgent compliance requirement into a strategic security advantage, positioning them to detect and respond to threats effectively as they scale operations across regulated markets.