GHSA-2J2X-HQR9-3H42

Vulnerability from github – Published: 2026-06-03 20:58 – Updated: 2026-08-04 21:26
VLAI
Summary
React Router's same-origin redirect with path starting // causes open redirect via protocol-relative URL reinterpretation
Details

Certain URLs passed to the redirect function can trigger an open redirect to an external domain depending on the level of validation done by the application prior to returning the redirect.

[!NOTE] This does not impact your React Router application if you are using Declarative Mode (<BrowserRouter>)

Severity
6.6 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U
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{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "react-router"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "7.0.0"
            },
            {
              "fixed": "7.14.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "react-router"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.7.0"
            },
            {
              "fixed": "6.30.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "@remix-run/router"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "1.3.0"
            },
            {
              "fixed": "1.23.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-40181"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-601"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-06-03T20:58:01Z",
    "nvd_published_at": "2026-06-02T20:16:35Z",
    "severity": "MODERATE"
  },
  "details": "Certain URLs passed to the `redirect` function can trigger an open redirect to an external domain depending on the level of validation done by the application prior to returning the `redirect`.\n\n\u003e [!NOTE]\n\u003e This does not impact your React Router application if you are using [Declarative Mode](https://reactrouter.com/start/modes#declarative) (`\u003cBrowserRouter\u003e`)",
  "id": "GHSA-2j2x-hqr9-3h42",
  "modified": "2026-08-04T21:26:09Z",
  "published": "2026-06-03T20:58:01Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/remix-run/react-router/security/advisories/GHSA-2j2x-hqr9-3h42"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-40181"
    },
    {
      "type": "WEB",
      "url": "https://github.com/remix-run/react-router/commit/d77f6b1"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/remix-run/react-router"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U",
      "type": "CVSS_V4"
    }
  ],
  "summary": "React Router\u0027s same-origin redirect with path starting // causes open redirect via protocol-relative URL reinterpretation"
}



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