performing-kubernetes-etcd-security-assessment

name	performing-kubernetes-etcd-security-assessment
description	Assesses the security posture of the etcd cluster backing Kubernetes: encryption at rest, TLS peer and client transport, access control, backup encryption, and network isolation. Use when auditing or hardening a control plane, reviewing whether Secrets are encrypted at rest, or protecting etcd backups, since etcd stores Secrets, RBAC policy, and ConfigMaps in plaintext by default. Keywords: etcd, EncryptionConfiguration, encryption at rest, peer TLS, snapshot, backup, control plane. Do not use for broad cluster-wide CIS checks - use performing-kubernetes-cis-benchmark-with-kube-bench.
domain	cybersecurity
subdomain	container-security
tags	["kubernetes","etcd","encryption","tls","security-assessment","backup","secrets","control-plane"]
version	1.0
author	mahipal
license	Apache-2.0
nist_csf	["PR.PS-01","PR.IR-01","ID.AM-08","DE.CM-01"]
mitre_attack	["T1610","T1611","T1609","T1525","T1573"]

Performing Kubernetes etcd Security Assessment

Overview

etcd is the distributed key-value store that serves as Kubernetes' backing store for all cluster data, including Secrets, RBAC policies, ConfigMaps, and workload configurations. Without proper hardening, etcd exposes all cluster secrets in plaintext, making it the highest-value target for attackers who gain control plane access. A comprehensive security assessment covers encryption at rest, TLS for transport, access control, backup security, and network isolation.

When to Use

• When conducting security assessments that involve performing kubernetes etcd security assessment
• When following incident response procedures for related security events
• When performing scheduled security testing or auditing activities
• When validating security controls through hands-on testing

Prerequisites

• Access to Kubernetes control plane nodes
• SSH access to etcd cluster nodes (or etcdctl configured)
• CIS Kubernetes Benchmark reference document
• Understanding of TLS certificate management and EncryptionConfiguration

Assessment Areas

1. Encryption at Rest

Verify that Kubernetes encrypts Secret data stored in etcd:

# Check if EncryptionConfiguration is configured on API server
ps aux | grep kube-apiserver | grep encryption-provider-config

# View the encryption configuration
cat /etc/kubernetes/enc/encryption-config.yaml

Expected secure configuration:

apiVersion: apiserver.config.k8s.io/v1
kind: EncryptionConfiguration
resources:
  - resources:
      - secrets
      - configmaps
    providers:
      - aescbc:
          keys:
            - name: key1
              secret: <base64-encoded-32-byte-key>
        {}