restrict-bind-escalate-impersonate.yaml

# Copyright 2024 Google LLC
#
# This is “Software” that is licensed under the “General Software” section of
# the Service Specific Terms (https://cloud.google.com/terms/service-terms) for
# usage in accordance with the following “Scope of Use”: This file may only be
# used on an Anthos cluster, including any associated ci/cd use. “Anthos
# cluster” is defined as “A Cluster (of any kind) registered to a fleet project
# where the Anthos API is enabled”.
apiVersion: constraints.gatekeeper.sh/v1beta1
kind: K8sRestrictRoleRules
metadata:
  name: cis-k8s-v1.7.1-restrict-bind-escalate-impersonate
  labels:
    policycontroller.gke.io/bundleName: cis-k8s-v1.7.1
  annotations:
    policycontroller.gke.io/bundleVersion: 202403.0-preview
    policycontroller.gke.io/constraintData: |-
      "{
        bundleName: 'cis-k8s-v1.7.1',
        bundleDisplayName: 'CIS Kubernetes Benchmark v1.7.1',
        bundleLink: 'https://cloud.google.com/anthos-config-management/docs/how-to/using-cis-k8s-benchmark',
        bundleVersion: '202403.0-preview',
        bundleDescription: 'Use the CIS Kubernetes Benchmark 1.7.1 policy bundle with Policy Controller to evaluate the compliance of your cluster resources against the CIS Kubernetes Benchmark, which is a set of recommendations for configuring Kubernetes to support a robust security posture.',
        controlNumbers: '[5.1.8]',
        severity: 'UNSPECIFIED',
        description: 'Restricts the access to the bind, escalate, impersonate on roles/clusterroles in `Roles` and `ClusterRoles`.',
        remediation: 'The access to roles/clusterroles with bind, escalate, impersonate in Roles and ClusterRoles is restricted. Remove bind, escalate, impersonate rules for clusterroles/roles from your Roles and ClusterRoles. See "RoleBinding and ClusterRoleBinding" for more information: https://kubernetes.io/docs/reference/access-authn-authz/rbac/#rolebinding-and-clusterrolebinding',
        minimumTemplateLibraryVersion: '1.15.2',
        constraintHash: '5cbc41cd74d8b7743eaf498a5bacf7fb6ec734d80e3c244481aac1eb44ebc7b6'
      }"
spec:
  enforcementAction: dryrun
  match:
    kinds:
      - apiGroups:
          - rbac.authorization.k8s.io
        kinds:
          - Role
          - ClusterRole
  parameters:
    disallowedRules:
      - apiGroups:
          - ""
        resources:
          - clusterroles
          - roles
        verbs:
          - bind
          - escalate
          - impersonate
    exemptions:
      clusterRoles:
        - name: admin
        - name: cluster-admin
        - name: system:controller:clusterrole-aggregation-controller
        - name: config-management-operator
      roles:
        - name: agent-updater
          namespace: gke-connect