Zero-Trust Cloud Hardening

An AWS environment had grown organically with overly permissive IAM roles, open security groups, and no continuous compliance monitoring. The attack surface was large and untracked. A security audit revealed multiple high-risk findings, prompting a comprehensive hardening initiative.

A defense-in-depth strategy was implemented: least-privilege IAM, network segmentation, CIS benchmark enforcement, continuous configuration scanning, and automated remediation. AWS Config rules evaluate every resource change in real time. GuardDuty provides threat detection. A set of Lambda functions automatically remediate common misconfigurations, with an audit trail of all actions.

IAM policies were analyzed with IAM Access Analyzer and rewritten to follow least-privilege. Security groups were audited and restricted to required ports and CIDR ranges. Terraform was used to enforce CIS benchmarks across all accounts. AWS Config rules were deployed to continuously check compliance, with Conftest policies adding an extra layer of policy-as-code. GuardDuty was enabled with custom suppression rules to reduce false positives.

All IAM roles now require session policies and MFA for elevated access. S3 buckets are encrypted with KMS and block public access by default. VPC flow logs are sent to a central logging account for forensic analysis. Secrets Manager rotates database credentials automatically. CloudTrail is enabled across all accounts with log file validation.

A Grafana dashboard aggregates findings from Config, GuardDuty, and Security Hub, showing compliance posture and active threats. Critical findings trigger PagerDuty alerts. A weekly compliance report is generated and sent to leadership. Drift detection alerts fire if resources are modified outside of Terraform.

The IAM attack surface was dramatically reduced. Continuous compliance monitoring replaced periodic manual audits. Automated remediation handles common misconfigurations without human intervention, and the organization has a real-time view of its security posture.