GKE Clusters Without Application-Layer Secrets Encryption

ID: gcloud-gke-secrets-encryption-disabled

Severity: high

Author: princechaddha

Tags: cloud,devops,gcp,gcloud,gke,kubernetes,security,encryption,secrets,gcp-cloud-config

Description

Ensure that encryption of Kubernetes secrets with Customer-Managed Keys (CMKs) is enabled for your Google Kubernetes Engine (GKE) clusters. Application-layer secrets encryption protects your Kubernetes secrets in etcd with an encryption key managed using the Cloud KMS service, providing an additional layer of security for sensitive data.

YAML Source

id: gcloud-gke-secrets-encryption-disabled

info:
  name: GKE Clusters Without Application-Layer Secrets Encryption
  author: princechaddha
  severity: high
  description: |
    Ensure that encryption of Kubernetes secrets with Customer-Managed Keys (CMKs) is enabled for your Google Kubernetes Engine (GKE) clusters. Application-layer secrets encryption protects your Kubernetes secrets in etcd with an encryption key managed using the Cloud KMS service, providing an additional layer of security for sensitive data.
  impact: |
    Without application-layer secrets encryption enabled, sensitive data stored in Kubernetes secrets is not protected against attackers who gain access to etcd backups or offline copies, potentially exposing confidential information.
  remediation: |
    Enable application-layer secrets encryption for your GKE clusters using Cloud KMS Customer-Managed Keys (CMKs):
    gcloud container clusters update CLUSTER_NAME --database-encryption-key=projects/PROJECT_ID/locations/LOCATION/keyRings/KEYRING/cryptoKeys/KEY
  reference:
    - https://cloud.google.com/kubernetes-engine/docs/how-to/encrypting-secrets
    - https://www.trendmicro.com/cloudoneconformity/knowledge-base/gcp/GKE/enable-application-layer-secrets-encryption.html
  tags: cloud,devops,gcp,gcloud,gke,kubernetes,security,encryption,secrets,gcp-cloud-config

flow: |
  code(1)
  for(let projectId of iterate(template.projectIds)){
    set("projectId", projectId)
    code(2)
    for(let cluster of iterate(template.clusters)){
      cluster = JSON.parse(cluster)
      set("clusterName", cluster.name)
      set("location", cluster.location)
      code(3)
    }
  }

self-contained: true

code:
  - engine:
      - sh
      - bash
    source: |
      gcloud projects list --format="json(projectId)"

    extractors:
      - type: json
        name: projectIds
        internal: true
        json:
          - '.[].projectId'

  - engine:
      - sh
      - bash
    source: |
      gcloud container clusters list --project $projectId --format="json(name,location)"

    extractors:
      - type: json
        name: clusters
        internal: true
        json:
          - '.[]'

  - engine:
      - sh
      - bash
    source: |
      gcloud container clusters describe $clusterName --location $location --project $projectId --format="yaml(databaseEncryption.keyName,conditions)"

    matchers:
      - type: word
        words:
          - "null"

    extractors:
      - type: dsl
        dsl:
          - '"GKE cluster " + clusterName + " in " + location + " of project " + projectId + " does not have application-layer secrets encryption enabled"'
# digest: 490a0046304402202771045ec2b4bbcbf932e03260b3e82aea3dd85078ff66c68cd5b58344a6d71e02207cdb11f9726d133062f33cdcce264536a1e9861c70ad6e12b2b573c5d482f2ea:922c64590222798bb761d5b6d8e72950

Guide to check the vulnerabilities

This template is used to detect vulnerabilities in web applications. It can be used with the Nuclei tool to scan for specific patterns or behaviors.

$ nuclei -u "URL" -t "cloud/gcp/gke/gcloud-gke-secrets-encryption-disabled.yaml"

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