Kyverno

Kyverno is a Kubernetes-native policy management tool that enables cluster administrators to define, enforce, and automate security and operational policies as Kubernetes resources. Unlike external policy engines that require complex integrations, Kyverno operates as an admission controller inside the cluster, allowing policies to be written as native Kubernetes Custom Resource Definitions (CRDs) using YAML manifests rather than a separate policy language. This approach means that anyone familiar with Kubernetes can create and manage policies without learning a new domain-specific language. Kyverno policies can validate, mutate, and generate Kubernetes resources, supporting use cases such as requiring security contexts, enforcing label standards, injecting sidecar containers, generating default NetworkPolicies and ConfigMaps, verifying image signatures using cosign, and restricting pod privileges. The tool provides comprehensive policy reports for compliance auditing and integrates with CI/CD pipelines to catch policy violations before resources reach the cluster. As a CNCF incubating project, Kyverno has gained significant adoption in the Kubernetes ecosystem, with over 5,800 GitHub stars and adoption by organizations ranging from startups to Fortune 500 enterprises. The project includes a CLI tool for testing policies locally, a VS Code extension for policy authoring, and pre-built policy libraries covering common compliance standards including CIS Kubernetes Benchmarks, NSA/CISA Kubernetes Hardening Guide, and PCI DSS requirements. Kyverno also supports background scanning of existing resources to identify and report violations, enabling continuous compliance monitoring.