The Kubernetes API server should validate that the service account token exists in etcd

kubernetes

Set up the kubernetes integration.

Description

Service accounts should be validated before validating the token. If --service-account-lookup is not enabled, the API server only verifies that the authentication token is valid, and does not validate that the service account token mentioned in the request is actually present in etcd. This enables you to use a service account token even after the corresponding service account is deleted.

Remediation

Edit the API server pod specification file /etc/kubernetes/manifests/kube-apiserver.yaml on the master node and set the below parameter. --service-account-lookup=true

NOTE: Alternatively, you can delete the --service-account-lookup parameter from this file so that the default takes effect.