Kubernetes’ First Major Security Hole Discovered
Kubernetes has become the most popular cloud container orchestration system by far, so it was only a matter of time until its first major security hole was discovered. And the bug, CVE-2018-1002105, aka the Kubernetes privilege escalation flaw, is a doozy. It’s a CVSS 9.8 critical security hole.
CVSS 9.8 critical security hole. With a specially crafted network request, any user can establish a connection through the Kubernetes application programming interface (API) server to a backend server. Once established, an attacker can send arbitrary requests over the network connection directly to that backend.
Adding insult to injury, these requests are authenticated with the Kubernetes API server’s Transport Layer Security (TLS) credentials. Worse still, ‘In default configurations, all users (authenticated and unauthenticated) are allowed to perform discovery API calls that allow this escalation.’ So, yes, anyone who knows about this hole can take command of your Kubernetes cluster.
Fortunately, there is a fix, but some of you aren’t going to like it. You must upgrade Kubernetes. Now.
Specifically, there are patched version of Kubernetes v1.10.11, v1.11.5, v1.12.3, and v1.13.0-rc.1.