Escaping Docker Containers

I recently came across this article describing 7 ways to escape a container.

You should read it if you’re conscious of your container security.

I want to point out that most of the listed container escape techniques require additional Linux capabilities.

You can set these capabilities in Kubernetes in a pod’s security context. Here’s what that might look like and link to the docs:

apiVersion: v1
kind: Pod
metadata:
  name: security-context-demo-4
spec:
  containers:
  - name: sec-ctx-4
    image: gcr.io/google-samples/node-hello:1.0
    securityContext:
      capabilities:
        add: ["NET_ADMIN", "SYS_TIME"]

It’s a huge security smell if you grant your Kubernetes workloads additional Linux capabilities.

Avoid adding additional capabilities unless you know what you’re doing and audit your cluster for any pods doing so.