Securing Your Kubernetes Clusters

Kubernetes security is complex but critical. Here are essential practices every team should implement.

Network Policies

Restrict pod-to-pod communication:

apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
  name: deny-all
spec:
  podSelector: {}
  policyTypes:
  - Ingress
  - Egress

RBAC Configuration

Implement least privilege:

apiVersion: rbac.authorization.k8s.io/v1
kind:Role
metadata:
  name: pod-reader
rules:
- apiGroups: [""]
  resources: ["pods"]
  verbs: ["get", "list"]

Pod Security Standards

Use pod security policies:

apiVersion: v1
kind: Pod
metadata:
  name: secure-pod
spec:
  securityContext:
    runAsNonRoot: true
    runAsUser: 1000
    fsGroup: 2000
  containers:
  - name: app
    securityContext:
      allowPrivilegeEscalation: false
      readOnlyRootFilesystem: true

Image Security

  • Use trusted registries
  • Scan images regularly
  • Sign images with Cosign
  • Implement admission controllers

Secrets Management

Never commit secrets: - Use Sealed Secrets - Implement Vault - Use cloud provider KMS - Rotate secrets regularly

Audit Logging

Enable and monitor audit logs:

apiVersion: audit.k8s.io/v1
kind: Policy
rules:
- level: Metadata

Supply Chain Security

  • Verify image signatures
  • Use SBOMs (Software Bill of Materials)
  • Implement policy engines (OPA, Kyverno)
  • Regular security scans

Security is a journey, not a destination. Stay vigilant!