1. 🔍 GuardDuty: Threat Detection
Continuous threat detection using ML-powered analysis of VPC Flow Logs, CloudTrail events, DNS logs.
Detection Capabilities: Compromised EC2 instances (malicious IP communication, crypto-mining activity), compromised IAM credentials (unusual API calls, credential exfiltration attempts), unauthorized reconnaissance (port scanning, brute force attacks), data exfiltration patterns (unusual S3 downloads, cross-region data transfers).
Alert Integration: Critical findings → SNS → CEO email + Slack. High-severity findings trigger incident response procedures (<30 minutes response time for critical). Medium/Low findings reviewed daily.
2024 Metrics: Zero actual threats detected (good news). 12 false positives investigated (authorized security testing). Average investigation time: 18 minutes per alert. Detection without disruption.
GuardDuty is early warning system. Most alerts are false positives (security tools testing, legitimate admin activity). But the one real alert justifies the cost.
2. 🛡️ Security Hub: Centralized Monitoring
Aggregated security findings from GuardDuty, Config, IAM Access Analyzer, Macie, Inspector across all AWS accounts.
Compliance Frameworks: AWS Foundational Security Best Practices (93% compliance), CIS AWS Foundations Benchmark v1.4 (89% compliance), PCI DSS v3.2.1 (N/A—no card processing). Automated compliance scoring with drift detection.
Automated Remediation: Critical findings auto-remediate via Lambda (S3 public access block, unencrypted EBS volumes, overly permissive security groups). Medium findings require CEO review. Low findings tracked for quarterly review.
Evidence Links: Security Hub dashboard provides audit trail for compliance validation. Config rules provide continuous compliance monitoring. CloudTrail provides event history for forensics.
Security Hub is single pane of glass. Without it, you're checking 8 different AWS security services manually. Centralization isn't luxury—it's operational necessity.
3. ⚙️ Config: Compliance Automation
Continuous configuration monitoring with automated compliance evaluation against custom rules.
Config Rules Enforced: S3 bucket encryption (AES-256 or KMS), S3 public access blocked (no public ACLs, no public bucket policies), RDS encryption at rest (all databases), EBS volume encryption (all volumes), security groups no unrestricted ingress (no 0.0.0.0/0 on sensitive ports), IAM password policy enforcement (min 14 chars, complexity requirements), MFA enabled for root account.
Compliance Dashboard: Real-time compliance status per rule. Non-compliant resources flagged immediately. Automated remediation for critical violations (Lambda-triggered fixes). Compliance history tracked for audit evidence.
2024 Compliance: 387 Config rule evaluations/day. 99.7% compliant resources (12 intentional exceptions documented in ISMS). Average time to remediate non-compliance: 4.2 hours. Drift detection prevents configuration decay.
Config is compliance automation. Manual compliance checks scale linearly with resources. Automated compliance checks scale to thousands of resources with same effort.
4. 🔐 KMS: Encryption Management
Centralized key management with hardware security modules (HSM) and automated rotation.
Encryption Strategy: All data encrypted at rest (S3, RDS, EBS, DynamoDB) using AWS KMS customer-managed keys. All data encrypted in transit (TLS 1.3 for HTTPS, TLS 1.2 minimum for AWS services). Key rotation: automatic annual rotation for customer-managed keys.
Key Hierarchy: Master keys per environment (production, staging, development). Service-specific data keys (database encryption, S3 bucket encryption, EBS volume encryption). IAM policy-based key access control (principle of least privilege, MFA for production key usage).
Compliance Integration: CloudTrail logs all KMS key usage (audit trail for compliance). Key policies enforce encryption requirements (S3 uploads must use KMS, RDS creation requires encryption). Automated alerts for key policy changes (CEO notification for production key modifications).
KMS is encryption without key management headaches. You don't rotate keys manually. You don't store keys in code. AWS handles HSM complexity. You handle access policies.
5. 🌐 VPC: Zero-Trust Segmentation
Multi-tier network architecture with security groups, NACLs, and private subnets.
Network Architecture: Public subnet (ALB/NLB, NAT Gateway, Bastion—if needed), Private app subnet (Lambda, ECS, EC2—application tier), Private data subnet (RDS, ElastiCache—no internet access), Management subnet (monitoring, logging—restricted access). See detailed architecture: Lambda in Private VPC.
Security Controls: Security groups (stateful, application-level, deny-by-default), NACLs (stateless, subnet-level, explicit deny rules), VPC Flow Logs (all traffic logged to CloudWatch, S3 retention 90 days), PrivateLink (AWS service access without internet gateway), VPC Peering (cross-region redundancy without public internet).
Zero-Trust Principle: No implicit trust between tiers. Application tier cannot directly access data tier (RDS proxy required). Public tier cannot access management tier. All cross-tier traffic logged and monitored. Assume breach, limit blast radius.
VPC segmentation is blast radius containment. Flat networks mean one compromised instance = entire infrastructure at risk. Multi-tier architecture means compromise requires multiple control failures.