kube-proxy and Pod Networking Security

Every Service you create in Kubernetes depends on a single component to make it reachable: kube-proxy. Running as a DaemonSet on every node, kube-proxy watches the API server for Service and EndpointSlice changes, then programs kernel-level packet forwarding rules so that a virtual ClusterIP actually routes traffic to backend Pods. That makes kube-proxy both essential infrastructure and a privileged attack surface. A compromised or misconfigured kube-proxy can redirect traffic, leak service topology, or bypass network segmentation entirely.

This lesson covers the three proxy modes and their security trade-offs, kube-proxy configuration hardening, and how NetworkPolicies backed by the right CNI plugin control pod-to-pod traffic. All three are explicit topics in the KCSA Cluster Component Security domain (22%).