Cluster Setup and Hardening
Securing a Kubernetes cluster begins with a hardened configuration across its core components. This section provides comprehensive best practices to secure the API server, control plane, network communication, nodes, pods, RBAC policies, secrets, and validates configurations. Each subsection maps to a common attack surface and includes mitigation guidance and practical tooling examples.
Following these practices reduces the risk of compromise, supports defense-in-depth, and helps meet compliance frameworks such as the CIS Kubernetes Benchmark.
CIS Benchmarks
Use CIS Benchmarks to validate your cluster's security posture:
API Server Security
Harden the Kubernetes API server to reduce exposure and control access:
- Compromised API Server Mitigation
- Misconfigured Admission Controllers Mitigation
- OPA/Gatekeeper
- Kyverno
Control Plane Security
Protect the cluster's core components and maintain data integrity:
Network Security
Control traffic flow, minimize exposure, and secure ingress/egress:
- DDoS Mitigation
- DNS Security
- Egress Control
- Exposed Dashboard Mitigation
- Ingress Security
- Network Policies
- Service Mesh Security
- Traffic Hijacking Mitigation
- Kube-Hunter
- Cilium
- Calico
- Kong
Node Security
Secure the infrastructure running your workloads:
Pod Security
Enforce strict security boundaries within workloads:
- AppArmor Profiles
- Compromised Sidecars Mitigation
- Container Escape Mitigation
- CSI Driver Mitigation
- Pod Sandboxing
- Pod Security Standards
- Seccomp in Pods
- Unrestricted hostPath Mitigation
- KubeAudit
RBAC and Identity
Use identity-aware access controls to enforce least privilege:
Secrets Management
Protect sensitive credentials and reduce the blast radius of compromise:
Configuration Validation
Validate YAML manifests and infrastructure code for misconfigurations before deployment:
Conclusion
Cluster setup and hardening is the foundation of Kubernetes security. Addressing the risks in each layer — from API access to pod isolation — allows you to build a resilient and secure infrastructure. The articles in this section provide actionable guidance to harden your cluster and protect against real-world threats.