Kubernetes 1.13 released, in which developers have eliminated the vulnerability of the illegal privilege escalation. The bug allowed to get full control over the cluster of containers.
To exploit the breach, it was necessary to send a specially designed discovery request to the backend API, which left the network connection open. This allowed access to the API server and send arbitrary commands to it. At the same time, the backend perceived requests as being sent by the server.
In addition, all Kubernetes users, including those who failed to authenticate, could use this flaw. As it turned out, the problem "stretches" from version 1.0.
To fix it, you need to update Kubernetes to versions 1.10.11, 1.11.5, 1.12.3 and 1.13.0 or at least block anonymous access to the API using the option --anonymous-auth = false, and also revoke the rights to perform exec operations / attach / portforward.
New Kubernates 1.13 features:
- The Container Storage interface has been stabilized to create plug-ins for various storage systems. The developers also stabilized a simplified interface for managing the Kubernetes cluster.
- TAVS container distribution planner, as well as the Kubelet Device Plugin Registration service, which provides access to the Kubelet from plug-ins.
- An experimental interface for creating plug-ins has been added, which allows integrating third-party monitoring systems into Kubernetes.
- The status of beta versions was obtained by APIServer DryRun, the Kubectl Diff team and the ability to use local block devices as permanent data stores.
- The default CoreDNS DNS server is now used.