GCP Kubernetes RBAC RoleBinding Create/Patch/Update/Delete Audit Events

Flags GCP audit events where Kubernetes RBAC RoleBindings/ClusterRoleBindings are created, modified, or removed.

FreeReviewedSigma · Medium · v4
Product
gcp
Service
gcp.audit
Author
Austin Songer @austinsonger (SigmaHQ), DRL 1.1
Published
2021-08-09
Updated
2026-07-31
title: GCP Kubernetes RBAC RoleBinding Create/Patch/Update/Delete Audit Events
id: 1e313674-e886-45d9-b0f7-98a69d2bcfc8
status: test
description: This rule identifies Kubernetes RBAC RoleBinding and ClusterRoleBinding changes in Google Cloud audit logs, including create, patch, update, and delete operations. Attackers may abuse RBAC modifications to grant unauthorized permissions and escalate access within a cluster. The detection relies on GCP audit telemetry that records Kubernetes authorization RPC method names for RBAC binding resource actions.
references:
  - https://github.com/elastic/detection-rules/pull/1267
  - https://kubernetes.io/docs/reference/kubernetes-api/authorization-resources/cluster-role-v1/#ClusterRole
  - https://cloud.google.com/kubernetes-engine/docs/how-to/role-based-access-control
  - https://kubernetes.io/docs/reference/access-authn-authz/rbac/
  - https://cloud.google.com/kubernetes-engine/docs/how-to/audit-logging
  - https://github.com/SigmaHQ/sigma/blob/master/rules/cloud/gcp/audit/gcp_kubernetes_rolebinding.yml
author: Austin Songer @austinsonger, Huntrule Team
date: 2021-08-09
modified: 2022-10-09
tags:
  - attack.credential-access
logsource:
  product: gcp
  service: gcp.audit
detection:
  selection:
    gcp.audit.method_name:
      - io.k8s.authorization.rbac.v*.clusterrolebindings.create
      - io.k8s.authorization.rbac.v*.rolebindings.create
      - io.k8s.authorization.rbac.v*.clusterrolebindings.patch
      - io.k8s.authorization.rbac.v*.rolebindings.patch
      - io.k8s.authorization.rbac.v*.clusterrolebindings.update
      - io.k8s.authorization.rbac.v*.rolebindings.update
      - io.k8s.authorization.rbac.v*.clusterrolebindings.delete
      - io.k8s.authorization.rbac.v*.rolebindings.delete
  condition: selection
falsepositives:
  - RoleBindings and ClusterRoleBinding being modified or deleted may be performed by a system administrator. Verify whether the user identity, user agent, and/or hostname should be making changes in your environment.
  - RoleBindings and ClusterRoleBinding modified or deleted from unfamiliar users should be investigated. If known behavior is causing false positives, it can be exempted from the rule.
level: medium
license: DRL-1.1
related:
  - id: 0322d9f2-289a-47c2-b5e1-b63c90901a3e
    type: derived