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GHSA-8V8X-CX79-35W7

Vulnerability from github – Published: 2026-01-08 20:50 – Updated: 2026-09-08 16:29
VLAI
Summary
React Router SSR XSS in ScrollRestoration
Details

A XSS vulnerability exists in in React Router's <ScrollRestoration> API in Framework Mode when using the getKey/storageKey props during Server-Side Rendering which could allow arbitrary JavaScript execution during SSR if untrusted content is used to generate the keys.

[!NOTE] This does not impact applications if developers have disabled server-side rendering in Framework Mode, or if they are using Declarative Mode (<BrowserRouter>) or Data Mode (createBrowserRouter/<RouterProvider>).

Severity
8.2 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N
Show details on source website
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{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "react-router"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "7.0.0"
            },
            {
              "fixed": "7.12.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "@remix-run/react"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.17.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-21884"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-79"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-01-08T20:50:05Z",
    "nvd_published_at": "2026-01-10T03:15:48Z",
    "severity": "HIGH"
  },
  "details": "A XSS vulnerability exists in in React Router\u0027s `\u003cScrollRestoration\u003e` API in [Framework Mode](https://reactrouter.com/start/modes#framework) when using the `getKey`/`storageKey` props during Server-Side Rendering which could allow arbitrary JavaScript execution during SSR if untrusted content is used to generate the keys.\n\n\u003e [!NOTE]\n\u003e This does not impact applications if developers have [disabled server-side rendering](https://reactrouter.com/how-to/spa) in Framework Mode, or if they are using [Declarative Mode](https://reactrouter.com/start/modes#declarative) (`\u003cBrowserRouter\u003e`) or [Data Mode](https://reactrouter.com/start/modes#data) (`createBrowserRouter`/`\u003cRouterProvider\u003e`).",
  "id": "GHSA-8v8x-cx79-35w7",
  "modified": "2026-09-08T16:29:55Z",
  "published": "2026-01-08T20:50:05Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/remix-run/react-router/security/advisories/GHSA-8v8x-cx79-35w7"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-21884"
    },
    {
      "type": "WEB",
      "url": "https://github.com/remix-run/react-router/pull/14705"
    },
    {
      "type": "WEB",
      "url": "https://github.com/remix-run/react-router/commit/c89c32c562a7723c45ee71dab1c892acaf7a608d"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:19712"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:3782"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:3958"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2026:3960"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/security/cve/CVE-2026-21884"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2428421"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/remix-run/react-router"
    },
    {
      "type": "WEB",
      "url": "https://github.com/remix-run/react-router/blob/react-router%407.12.0/CHANGELOG.md#v7120"
    },
    {
      "type": "WEB",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-21884.json"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "React Router SSR XSS in ScrollRestoration"
}



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