A flaw was found in the Konnectivity proxy-server configuration for hosted control planes. The agent-facing listener was started without --cluster-ca-cert (and without token-based agent authentication), so client certificates were not validated. A remote attacker who can reach the Konnectivity cluster endpoint could connect as an unauthenticated agent, join the routing pool, and potentially proxy, inspect, modify, or drop control-plane-to-node traffic.
Until an update that configures Konnectivity agent authentication is applied, restrict network access to the Konnectivity cluster (agent) endpoint so that only trusted worker networks can reach it. For NodePort or LoadBalancer publishing, limit ingress to port 8091 to worker node subnet ranges. For Route-based publishing, restrict access to the Konnectivity route to trusted networks where possible. These controls reduce the chance that an unauthenticated attacker can reach the agent listener; they do not replace proper agent client-certificate (or token) authentication.