multicluster engine for Kubernetes 2.1 vulnerability

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.

Published 20 Jul 2026Updated 5 Sep 202619 sources
CVSS 9.4

What happened

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.

Affected versions

multicluster engine for Kubernetes 2.1: See vendor advisory Fixed: See vendor advisory.

Why it matters

Review the vendor advisory and exposure of the affected product to determine operational impact.

Detection & mitigation

  • Apply vendor-provided updates or mitigations.
  • Review affected product exposure and access logs.

Public PoC references

No public PoC reference has passed the current publication threshold.