Nixpkgs security tracker

Untriaged

Permalink CVE-2026-61682

9.9 CRITICAL

CVSS version (CVSS): 3.1
Attack Vector (AV): Network (N)
Attack Complexity (AC): Low (L)
Privileges Required (PR): Low (L)
User Interaction (UI): None (N)
Scope (S): Changed (C)
Confidentiality (C): High (H)
Integrity (I): High (H)
Availability (A): High (H)
Modified Attack Vector (MAV): Network (N)
Modified Attack Complexity (MAC): Low (L)
Modified Privileges Required (MPR): Low (L)
Modified User Interaction (MUI): None (N)
Modified Confidentiality (MC): High (H)
Modified Scope (MS): Changed (C)
Modified Integrity (MI): High (H)
Modified Availability (MA): High (H)

created 3 days, 4 hours ago Activity log

Created suggestion 3 days, 4 hours ago

kcp front-proxy does not strip inbound X-Remote-* identity headers, allowing any authenticated client to inject groups/warrants and impersonate system:masters in any workspace

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.