Firewalls are not enough. Inside a Kubernetes cluster, silent traffic can move between pods unchecked, creating hidden attack paths. Kubernetes Network Policies close these paths by defining what pods can talk to each other — and just as important, what they cannot. But when third-party components live in your cluster, every open connection is a new risk vector.
A Kubernetes Network Policies third-party risk assessment starts with mapping all inbound and outbound flows. Identify every third-party service, library, or container image. Check which namespaces they touch and which pod labels they match. If a vendor’s pod can reach sensitive workloads without policy restrictions, that is a high-risk finding.
Next, enforce least privilege. Write NetworkPolicies that limit third-party pods to only the IP blocks, ports, and protocols they require. For example, if an analytics service only needs HTTP access to a specific API pod, block everything else at the cluster level. Keep policies namespace-scoped when possible to prevent lateral movement.