GCP Kubernetes Rolebindings Created or Patched

Elastic Stack Serverless Security

Identifies the creation or patching of potentially malicious role bindings. Users can use role bindings and cluster role bindings to assign roles to Kubernetes subjects (users, groups, or service accounts).

Rule type: query

Rule indices:

• filebeat-*
• logs-gcp*

Severity: medium

Risk score: 47

Runs every: 5m

Searches indices from: now-20m (https://www.elastic.co/guide/en/elasticsearch/reference/current/common-options.html#date-math[Date Math format], see also Additional look-back time)

Maximum alerts per execution: 100

References:

• https://cloud.google.com/kubernetes-engine/docs/how-to/audit-logging
• https://unofficial-kubernetes.readthedocs.io/en/latest/admin/authorization/rbac/
• https://cloud.google.com/kubernetes-engine/docs/how-to/role-based-access-control

Tags:

• Elastic
• Cloud
• GCP
• Continuous Monitoring
• SecOps
• Configuration Audit

Version: 2

Rule authors:

• Elastic
• Austin Songer

Rule license: Elastic License v2

The GCP Fleet integration, Filebeat module, or similarly structured data is required to be compatible with this rule.

event.dataset:(googlecloud.audit or gcp.audit) and event.action:(io.k8s.authorization.rbac.v*.clusterrolebindings.create or
io.k8s.authorization.rbac.v*.rolebindings.create or io.k8s.authorization.rbac.v*.clusterrolebindings.patch or
io.k8s.authorization.rbac.v*.rolebindings.patch) and event.outcome:success and
not gcp.audit.authentication_info.principal_email:"system:addon-manager"

Framework: MITRE ATT&CKTM

• Tactic:

  • Name: Privilege Escalation
  • ID: TA0004
  • Reference URL: https://attack.mitre.org/tactics/TA0004/