cyber-security-resources/docker-and-k8s-security/kubernetes/secrets.md

Kubernetes Secrets

While Kubernetes Secrets provide a convenient way to manage sensitive information within a Kubernetes cluster, there are alternative solutions that you can consider based on your specific requirements:

1. External Secrets Management Systems:

   • Use external secrets management systems such as HashiCorp Vault or Azure Key Vault.
   • These systems provide enhanced security features, centralized management, and fine-grained access control for secrets.
   • Kubernetes can integrate with these systems through plugins or custom controllers to fetch secrets during runtime.

2. Configuration Management Tools:

   • Leverage configuration management tools like Ansible, Puppet, or Chef to manage and distribute secrets to Kubernetes clusters.
   • These tools offer more advanced features for secret rotation, versioning, and auditing.
   • Secrets can be encrypted and securely stored in the configuration management system, and then retrieved during deployment or runtime.

3. Encrypted Environment Variables:

   • Instead of using Kubernetes Secrets, you can encrypt sensitive information and store them as environment variables within the Pod specification.
   • Encryption can be achieved using tools like SOPS or using built-in encryption capabilities of your deployment automation or configuration management tool.

4. External Key Management Services:

   • Utilize external key management services like AWS Key Management Service (KMS) or Google Cloud Key Management Service (KMS) for managing encryption keys.
   • Encrypt the secrets outside of Kubernetes and store them in a secure key management service.
   • Retrieve the encrypted secrets during runtime and decrypt them within the application.

5. Infrastructure-as-Code Techniques:

   • Apply infrastructure-as-code practices to manage secrets outside of Kubernetes manifests.
   • Store secrets securely in version-controlled configuration files (e.g., YAML, JSON, or encrypted files) alongside your infrastructure code.
   • During the deployment process, the secrets are injected into the appropriate Kubernetes resources.

These alternatives provide different levels of security, flexibility, and integration options for managing sensitive information in Kubernetes. The choice depends on factors such as the level of security required, compliance regulations, ease of management, and integration with existing systems. It is essential to assess your specific needs and evaluate the trade-offs before selecting the most suitable alternative for your use case.

Comparing HashiCorp Vault and Azure Key Vault

Feature	Calico	Cilium
Architecture	Layer 3 approach with BGP routing	Combination of Layer 3 and
		Layer 4/Layer 7 proxy-based
		networking and policy
Network Policy	Robust network policy support	Advanced network policy
Management	and integration with Kubernetes	capabilities including HTTP/HTTPS
		and gRPC-layer filtering
Security	Distributed firewall model with	Deep packet inspection,
	ingress and egress filtering	identity-based access controls,
		application-layer security
Scalability	Designed to scale to thousands of nodes	High scalability and
	and handle large-scale deployments	performance for large
		Kubernetes clusters
Service Mesh	Can be used as a foundation for	Built-in service mesh
Integration	integrating with service mesh solutions	functionality with support
	like Istio	for Envoy and Istio
Performance	High-performance networking and	Efficient packet processing and
	forwarding with low latency	low latency communication
Observability	Network flow logs, policy auditing,	Advanced observability features
	and visibility into network traffic	including detailed network flow
		logs, service mesh observability
		and tracing
Community	Large and active community backed	Growing community and strong
	by Project Calico and Tigera	industry support