Image Registries and Repository Security

Any pod can pull any image from any registry. That is the default security posture of every Kubernetes cluster. No signature checks, no registry allowlists, no vulnerability gates. If an attacker pushes a malicious image to a public registry and someone references it in a Deployment, Kubernetes will happily pull and run it.

Registry security is where your supply chain meets your cluster. The previous article covered the broader supply chain, from source code to build artifacts. This article narrows the focus to the registry layer itself: how Kubernetes authenticates to registries, how you scan and sign images before they reach workloads, and how admission policies enforce that only approved images are allowed to run.