A flaw was found in the Kubernetes API server, where it allows an attacker to escalate their privileges from a compromised node. This flaw allows an attacker who can intercept requests on a compromised node, to redirect those requests, along with their credentials, to perform actions on other endpoints that trust those credentials (including other clusters), allowing for escalation of privileges. The highest threat from this vulnerability is to confidentiality, integrity, and system availability.
Default access permissions for Persistent Volumes (PVs) created by the Kubernetes Azure cloud provider in versions 1.6.0 to 1.6.5 are set to "container" which exposes a URI that can be accessed without authentication on the public internet. Access to the URI string requires privileged access to the Kubernetes cluster or authenticated access to the Azure portal.