Minimize access to create pods (RBAC)

The ability to create pods in a namespace can provide a number of opportunities for privilege escalation, such as assigning privileged service accounts to these pods or mounting hostPaths with access to sensitive data (unless Pod Security Policies are implemented to restrict this access). As such, access to create new pods should be restricted to the smallest possible group of users. The ability to create pods in a cluster opens up possibilities for privilege escalation and should be restricted, where possible.

Risk Level: Low
Cloud Entity: Kubernetes Role Binding
CloudGuard Rule ID: D9.K8S.IAM.35
Covered by Spectral: Yes
Category: Security, Identity, & Compliance

GSL LOGIC

KubernetesRoleBinding should not have role.rules contain [ (verbs with ['create'] and (resources with ['pod'] or resources with ['%*%'])) or (verbs with ['%*%'] and (resources with ['pod'] or resources with ['%*%']))]

REMEDIATION

Where possible, remove create access to pod objects in the cluster.

Kubernetes Role Binding

A role binding grants the permissions defined in a role to a user or set of users. It holds a list of subjects (users, groups, or service accounts), and a reference to the role being granted. A RoleBinding grants permissions within a specific namespace whereas a ClusterRoleBinding grants that access cluster-wide.

Compliance Frameworks

  • CIS Amazon Elastic Kubernetes Service (EKS) Benchmark v1.0.1
  • CIS Amazon Elastic Kubernetes Service (EKS) Benchmark v1.1.0
  • CIS Amazon Elastic Kubernetes Service (EKS) Benchmark v1.2.0
  • CIS Amazon Elastic Kubernetes Service (EKS) Benchmark v1.3.0
  • CIS Google Kubernetes Engine (GKE) Benchmark v1.2.0
  • CIS Google Kubernetes Engine (GKE) Benchmark v1.4.0
  • CIS Kubernetes Benchmark v1.20
  • CIS Kubernetes Benchmark v1.23
  • CIS Kubernetes Benchmark v1.24
  • CIS Kubernetes Benchmark v1.5.1
  • CIS Kubernetes Benchmark v1.6.1
  • CIS Microsoft Kubernetes Engine (AKS) Benchmark v1.1.0
  • CIS Microsoft Kubernetes Engine (AKS) Benchmark v1.3.0
  • CIS OpenShift Container Platform v4 Benchmark v1.1.0
  • CIS OpenShift Container Platform v4 Benchmark v1.4.0
  • Kubernetes NIST.SP.800-190
  • Kubernetes v.1.13 CloudGuard Best Practices
  • Kubernetes v.1.14 CloudGuard Best Practices
  • OpenShift Container Platform v3