Traefik before 3.6.23 IngressRouteTCP ServersTransport Namespace Bypass

{
  "id": "8bd077ddb51d5cced0c3a08d56017cedb644a61449767b7b7d9d16cdd50baa07",
  "url": "https://osv.dev/vulnerability/CVE-2026-65602",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Traefik before 3.6.23 IngressRouteTCP ServersTransport Namespace Bypass",
    "summary": "Traefik 3.6.0 through 3.6.22 and 3.7.0 through 3.7.6 fail to enforce the crossProviderNamespaces allowlist for IngressRouteTCP service serversTransport references (the allowlist was only enforced for HTTP serversTransport references). A low-privileged Kubernetes user in a namespace not listed in crossProviderNamespaces can set serversTransport: foo@file on an IngressRouteTCP service, causing Traefik to accept the forbidden cross-provider reference and use a file-provider TCPServersTransport — including privileged backend mTLS client certificates, SPIFFE identity, or PROXY-protocol settings. This is fixed in 3.6.23 and 3.7.7.",
    "evidence": "osv:CVE-2026-65602",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2026-65602",
      "aliases": [
        "CVE-2026-65602",
        "GHSA-42cj-m3vj-89wv",
        "GO-2026-6192"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/traefik/traefik",
              "type": "GIT",
              "events": [
                {
                  "introduced": "06db5168c0d936a0716cbede56bc2cd332be0d4f"
                },
                {
                  "fixed": "84d4e8b139d1ac5e5b2d250fff95baed5ba0584f"
                },
                {
                  "introduced": "04aa6bb4f9776f2ba87e5cd181d250e3610e6419"
                },
                {
                  "fixed": "b2c18b1e39fbe2099e4dce927e4e6e56674ede0f"
                },
                {
                  "fixed": "26c96a3935cafb473f4a5bae1886560d9aa4e4f0"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "3.6.0"
                      },
                      {
                        "fixed": "3.6.23"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "cpe": "cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "3.7.0"
                      },
                      {
                        "fixed": "3.7.7"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "range": [
                      {
                        "fixed": "26c96a3935cafb473f4a5bae1886560d9aa4e4f0"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  }
                ]
              }
            }
          ],
          "versions": [
            "v3.6.22",
            "v3.6.21",
            "v3.6.20",
            "v3.7.4",
            "v3.7.3",
            "v3.6.19",
            "v3.7.2",
            "v3.6.18",
            "v3.6.17",
            "v3.7.1",
            "v3.6.16",
            "v3.7.0",
            "v3.6.15",
            "v3.6.14",
            "v3.6.13",
            "v3.6.12",
            "v3.6.11",
            "v3.6.10",
            "v3.6.9",
            "v3.6.8",
            "v3.6.7",
            "v3.6.6",
            "v3.6.5",
            "v3.6.4",
            "v3.6.3",
            "v3.6.2",
            "v3.6.1",
            "v3.6.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-65602.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:50.451368957Z",
      "provider": "osv",
      "references": [
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/65xxx/CVE-2026-65602.json",
        "https://github.com/traefik/traefik/security/advisories/GHSA-42cj-m3vj-89wv",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-65602",
        "https://www.vulncheck.com/advisories/traefik-before-ingressroutetcp-serverstransport-namespace-bypass",
        "https://github.com/traefik/traefik/commit/26c96a3935cafb473f4a5bae1886560d9aa4e4f0"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-863"
        ],
        "cna_assigner": "VulnCheck",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/65xxx/CVE-2026-65602.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-65602",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 518770,
  "published_at": "2026-07-22T11:21:48.127+00:00"
}