Prevent data exfiltration: AWS egress controls for cloud workloads

This article presents a layered egress control architecture using AWS services to prevent unauthorized data exfiltration from cloud workloads and AI agents.

• Hub-and-spoke network pattern with Transit Gateway routes internet traffic through AWS Network Firewall for centralized inspection
• Route 53 Resolver DNS Firewall blocks DNS tunneling and unauthorized domain queries before connections establish
• Data perimeters using SCPs, RCPs, and VPC endpoint policies restrict API-level access to trusted resources within your organization
• GuardDuty detects behavioral anomalies and exfiltration attempts; IAM Access Analyzer identifies externally accessible resources
• Security Hub correlates findings across services; automated remediation via EventBridge and Lambda updates firewall rules in real time
• Phased implementation approach: Phase 1 enables DNS Firewall and GuardDuty; Phase 2 deploys data perimeters and Network Firewall; Phase 3 adds continuous monitoring and automation

Egress security requires layered preventive and detective controls applied equally to traditional workloads and AI agents to close outbound blind spots and prevent unauthorized data transfer.