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Profile Applicability: Level 2
Kubernetes provides a default namespace, where objects are placed if no namespace is specified for them. Placing objects in this namespace makes application of RBAC and other controls more difficult.
Resources in a Kubernetes cluster should be segregated by namespace, to allow for security controls to be applied at that level and to make it easier to manage resources.
Note
Note
Unless a namespace is specific on object creation, the default namespace will be used.

Audit

Run this command to list objects in default namespace:
kubectl get all -n default
The only entries there should be system managed resources such as the kubernetes service.

Remediation

Ensure that namespaces are created to allow for appropriate segregation of Kubernetes resources and that all new resources are created in a specific namespace.