CVE-2026-61682

Summary

kcp is a Kubernetes-like control plane for form-factors and use-cases beyond Kubernetes and container workloads. Prior to 0.31.4 and 0.32.2, the kcp front-proxy does not remove inbound X-Remote-User, X-Remote-Group, or X-Remote-Extra-* identity headers before forwarding requests to shards. Any authenticated tenant can inject X-Remote-Group: system:masters, authorization.kcp.io/warrant, authentication.kcp.io/scopes, or a group used for per-workspace required-group gating, and the shard trusts these values as authenticated identity assertions. This allows cross-workspace impersonation, authorization bypass, and arbitrary reading, writing, or deletion of resources, secrets, RBAC data, APIExports, APIBindings, and LogicalClusters. This issue is fixed in versions 0.31.4 and 0.32.2.

Affected Software

VendorProductVersion RangeStatus
kcp-devkcp< 0.31.4affected
kcp-devkcp>= 0.32.0, < 0.32.2affected

Weaknesses

  • CWE-290: CWE-290: Authentication Bypass by Spoofing
  • CWE-302: CWE-302: Authentication Bypass by Assumed-Immutable Data
  • CWE-348: CWE-348: Use of Less Trusted Source

References