A flaw was found in atomic-openshift of openshift-4.2 where the basic-user RABC role in OpenShift Container Platform doesn't sufficiently protect the GlusterFS StorageClass against leaking of the restuserkey. An attacker with basic-user permissions is able to obtain the value of restuserkey, and use it to authenticate to the GlusterFS REST service, gaining access to read, and modify files.

During installation of an OpenShift 4 cluster, the openshift-install command line tool creates an auth directory, with kubeconfig and kubeadmin-password files. Both files contain credentials used to authenticate to the OpenShift API server, and are incorrectly assigned word-readable permissions.

In contrast, the oc command line tool creates configuration files that are only readable by the current user.