Open-Source Tool 'zombiescan' Audits AWS Accounts for Unused, Costly Resources

A developer has released zombiescan, a free open-source Python tool that scans AWS accounts to identify idle or orphaned resources that continue to incur charges without serving any workload. The tool checks 22 categories of resources — including unattached EBS volumes, idle NAT gateways, unassociated Elastic IPs, and stopped RDS instances — and prices each finding using the AWS Price List API. Seventeen of the 22 resource types carry a direct monthly cost, while the remaining five are flagged because they accumulate silently and can block future deletions. The tool operates entirely in read-only mode, making no changes to any resource, and can scan 17 regions across all 22 checks in roughly 20 seconds on a small account. It requires standard AWS credentials and read access covered by the managed ReadOnlyAccess policy, and can be installed directly from its GitHub repository.