CVE-2026-71208 PUBLISHED

KubeSphere: SSRF via Unvalidated Cluster CRD Connection Endpoint in Cluster Reconciliation

Assigner: TuranSec
Reserved: 05.08.2026 Published: 05.08.2026 Updated: 05.08.2026

KubeSphere's cluster-controller reconciliation (pkg/utils/clusterclient/clusterclient.go, addCluster) processes every Cluster custom resource's connection configuration and immediately calls Discovery().ServerVersion() against the CRD-specified Kubernetes API endpoint, which is parsed only for URL syntax (url.Parse) with no allow/deny-list for loopback, RFC1918 private ranges, link-local, or cloud-metadata addresses (e.g. 169.254.169.254). A user able to create or update a Cluster CRD can force the controller-manager and apiserver pods to issue outbound requests to arbitrary internal or metadata endpoints.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
CVSS Score: 6.5

Product Status

Vendor kubesphere
Product KubeSphere
Versions Default: unknown
  • affected from 4.0.0 to 4.1.3-rc.0 (incl.)

Credits

  • Ashik Mohamed finder

References

Problem Types

  • CWE-918 Server-Side Request Forgery (SSRF) CWE