cfn-nag vs KICS

cfn-nag is free, MIT-licensed software that scans AWS CloudFormation templates for patterns that may indicate insecure infrastructure. It checks for overly permissive IAM policies and security-group rules, disabled access logging or encryption, and password literals. The scanner accepts JSON, .template, YAML, and YML files, and recursively processes subdirectories when given a directory. Results print to standard output, with JSON output available; failures return a non-zero exit code while warnings return success. Installation is documented through RubyGems and Homebrew, with Ruby 2.5 or later required for gem installation. A Dockerfile and Docker Hub image are provided. cfn-nag can run in GitHub Actions and AWS CodePipeline. Profiles, deny lists, per-resource suppressions, and custom rules support policy tailoring. Static analysis needs supplied parameter values to assess them and does not inspect false Fn::If outcomes by default.

KICS is a free, open-source static analysis solution powered by Checkmarx. It scans Infrastructure as Code for security vulnerabilities, compliance issues, and configuration mistakes across Terraform, Kubernetes, Docker, AWS CloudFormation, Ansible, Helm, Google Deployment Manager, AWS SAM, Microsoft ARM, Azure Blueprints, OpenAPI, Pulumi, Crossplane, Knative, and Serverless Framework files. Its security queries can be edited, extended, or supplemented with new queries, using OPA Rego policy language. Documented CI and delivery integrations include GitHub Actions, GitLab CI, Jenkins, Azure Pipelines, CircleCI, Bitbucket Pipelines, Terraform Cloud, AWS CodeBuild, pre-commit hooks, and others. A Visual Studio Code extension can scan automatically. KICS runs as a Docker image, from source, or through downloadable Linux, Windows, and macOS releases. Reports can be exported as JSON, SARIF, GitLab SAST, JUnit, HTML, PDF, CycloneDX, ASFF, or CSV. Terraform functions and environment variables are unsupported, and unofficial or custom Terraform modules are not supported.