Information
The RBAC role 'cluster-admin' provides wide-ranging powers over the environment and should be used only where and when needed.
Rationale:
Kubernetes provides a set of default roles where RBAC is used. Some of these roles such as 'cluster-admin' provide wide-ranging privileges which should only be applied where absolutely necessary. Roles such as 'cluster-admin' allow super-user access to perform any action on any resource. When used in a 'ClusterRoleBinding', it gives full control over every resource in the cluster and in all namespaces. When used in a 'RoleBinding', it gives full control over every resource in the rolebinding's namespace, including the namespace itself.
NOTE: Nessus has provided the target output to assist in reviewing the benchmark to ensure target compliance.
Solution
Identify all clusterrolebindings to the cluster-admin role. Check if they are used and if they need this role or if they could use a role with fewer privileges.
Where possible, first bind users to a lower privileged role and then remove the clusterrolebinding to the cluster-admin role :
kubectl delete clusterrolebinding [name]