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

{
  "id": "92f08c413fd2c371ced0b70df258b9e6aed7090cfd14c05f9f8afe7382ce3a4d",
  "url": "https://osv.dev/vulnerability/CVE-2026-71208",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "KubeSphere - SSRF via Unvalidated Cluster CRD Connection Endpoint in Cluster Reconciliation",
    "summary": "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).",
    "evidence": "osv:CVE-2026-71208",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2026-71208",
      "aliases": [
        "CVE-2026-71208"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/kubesphere/kubesphere",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "last_affected": "887496e7464bfd9bbab71a274340ea9c0b51a060"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "4.0.0"
                      },
                      {
                        "last_affected": "4.1.3-rc.0"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StandardRange"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v4.1.3-rc.0",
            "helm-chart-1.1.3",
            "v4.1.2",
            "helm-chart-1.1.2",
            "v4.1.1",
            "v3.4.0",
            "v3.4.0-rc.0",
            "v3.3.0-rc.3",
            "v3.3.0",
            "v3.3.0-rc.2",
            "v3.3.0-rc.1",
            "v3.3.0-rc.0",
            "v3.3.0-alpha.1",
            "v3.3.0-alpha.0",
            "v3.2.0",
            "v3.2.0-rc.1",
            "v3.2.0-alpha.1",
            "v3.2.0-alpha.0",
            "v3.1.0",
            "v3.1.0-alpha.0",
            "v3.0.0",
            "v2.1.0",
            "advanced-2.0.2",
            "advanced-2.0.0",
            "advanced-1.0.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-71208.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:34.874814487Z",
      "provider": "osv",
      "references": [
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/71xxx/CVE-2026-71208.json",
        "https://github.com/ashikmd7/kubeSphere/blob/main/SSRF%20via%20Cluster%20CRD%20KubeConfig/README.md",
        "https://github.com/kubesphere/kubesphere",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-71208"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-918"
        ],
        "cna_assigner": "TuranSec",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/71xxx/CVE-2026-71208.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-71208",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 501952,
  "published_at": "2026-08-05T06:59:13.308+00:00"
}