Description
Skipper is an HTTP router and reverse proxy for service composition. Prior to 0.27.13, the routesrv component serves cluster-wide control-plane data without application-layer authentication through /routes, /routes/{zone}, /swarm/redis/shards, and /swarm/valkey/shards. The handlers registered in routesrv/routesrv.go, eskipBytes.ServeHTTP in routesrv/eskipbytes.go, RedisHandler.ServeHTTP in routesrv/redishandler.go, and ValkeyHandler.ServeHTTP in routesrv/valkeyhandler.go only restrict HTTP methods and do not authenticate callers. A compromised or otherwise attacker-controlled pod that can reach routesrv on the Kubernetes cluster network can bypass its namespace-scoped RBAC and read Ingress and RouteGroup backend URLs, filter-chain and OAuth or OIDC path details, and Redis or Valkey shard addresses across namespaces. NetworkPolicy can restrict reachability but does not remove the missing-authentication condition, and the established impact is confidentiality exposure rather than direct integrity or availability loss. This issue is fixed in version 0.27.13.
Published: 2026-09-14
Score: 5.7 Medium
EPSS: n/a
KEV: No
Impact: n/a
Action: n/a
AI Analysis

No analysis available yet.

Remediation

No remediation available yet.

Tracking

Sign in to view the affected projects.

Advisories
Source ID Title
Github GHSA Github GHSA GHSA-5587-2x54-jj6h Skipper's routesrv-no-auth component: All routesrv API Endpoints Lack Authentication
History

Tue, 15 Sep 2026 05:00:00 +0000

Type Values Removed Values Added
First Time appeared Zalando
Zalando skipper
Vendors & Products Zalando
Zalando skipper

Mon, 14 Sep 2026 21:00:00 +0000

Type Values Removed Values Added
Description Skipper is an HTTP router and reverse proxy for service composition. Prior to 0.27.13, the routesrv component serves cluster-wide control-plane data without application-layer authentication through /routes, /routes/{zone}, /swarm/redis/shards, and /swarm/valkey/shards. The handlers registered in routesrv/routesrv.go, eskipBytes.ServeHTTP in routesrv/eskipbytes.go, RedisHandler.ServeHTTP in routesrv/redishandler.go, and ValkeyHandler.ServeHTTP in routesrv/valkeyhandler.go only restrict HTTP methods and do not authenticate callers. A compromised or otherwise attacker-controlled pod that can reach routesrv on the Kubernetes cluster network can bypass its namespace-scoped RBAC and read Ingress and RouteGroup backend URLs, filter-chain and OAuth or OIDC path details, and Redis or Valkey shard addresses across namespaces. NetworkPolicy can restrict reachability but does not remove the missing-authentication condition, and the established impact is confidentiality exposure rather than direct integrity or availability loss. This issue is fixed in version 0.27.13.
Title Skipper routesrv-no-auth: All routesrv API Endpoints Lack Authentication
Weaknesses CWE-306
References
Metrics cvssV3_1

{'score': 5.7, 'vector': 'CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-09-14T20:03:14.613Z

Reserved: 2026-06-12T16:25:43.085Z

Link: CVE-2026-54246

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-09-14T20:16:45.697

Modified: 2026-09-14T20:16:45.697

Link: CVE-2026-54246

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-09-15T04:45:11Z

Weaknesses
  • CWE-306

    Missing Authentication for Critical Function