React Router: Cross-site Scripting is Possible due to Missing RSCErrorHandler Protocol Validation (Incomplete fix for CVE-2026-53667)

{
  "id": "ec0722c45899fcb6628b66a26244a52a8241cd793007c6f3e944167cf2241bcc",
  "url": "https://osv.dev/vulnerability/CVE-2026-53667",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "React Router: Cross-site Scripting is Possible due to Missing RSCErrorHandler Protocol Validation (Incomplete fix for CVE-2026-53667)",
    "summary": "React Router is a router for React. In versions 7.11.0 through 7.17.0, the RSCErrorHandler is missing protocol validation, allowing for redirects from untrusted sources. This issue is a follow up to CVE-2026-53667, and only affects consuming applications if they are using the unstable RSC APIs. This issue has been fixed in version 7.18.0.",
    "evidence": "osv:CVE-2026-53667",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2026-53667",
      "aliases": [
        "CVE-2026-53667",
        "GHSA-h8fp-f39c-q6mh"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:L/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/remix-run/react-router",
              "type": "GIT",
              "events": [
                {
                  "introduced": "b34a9cd1f74231ded97c1e6ca9dff8f09a1b87ca"
                },
                {
                  "fixed": "24283e93971e3e4f9f909c0bae63583f173fcd52"
                },
                {
                  "fixed": "ce596e823f0d7b883a433af1d5a839a8b9fe0242"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:shopify:react-router:*:*:*:*:*:node.js:*:*",
                    "range": [
                      {
                        "introduced": "7.11.0"
                      },
                      {
                        "fixed": "7.18.0"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "range": [
                      {
                        "fixed": "ce596e823f0d7b883a433af1d5a839a8b9fe0242"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "fixed": "24283e93971e3e4f9f909c0bae63583f173fcd52"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "react-router@7.18.0"
                  }
                ]
              }
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-53667.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:53.342405186Z",
      "provider": "osv",
      "references": [
        "https://github.com/remix-run/react-router/blob/main/CHANGELOG.md#v7180",
        "https://github.com/remix-run/react-router/releases/tag/react-router@7.18.0",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53667.json",
        "https://github.com/remix-run/react-router/security/advisories/GHSA-h8fp-f39c-q6mh",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-53667",
        "https://github.com/remix-run/react-router/commit/ce596e823f0d7b883a433af1d5a839a8b9fe0242",
        "https://github.com/remix-run/react-router/pull/15177"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-79"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53667.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-53667",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 522336,
  "published_at": "2026-07-27T21:21:16.084+00:00"
}