{
"id": "GHSA-rxv8-25v2-qmq8",
"aliases": [
"CVE-2026-34077"
],
"details": "A DoS vulnerability exists in the React Router v7 [Framework Mode](https://reactrouter.com/start/modes#framework), as well as Remix v2.9.0+ with [Single Fetch](https://v2.remix.run/docs/guides/single-fetch) enabled. In some scenarios the underlying serialization algorithm can become a bottleneck when encoding specific types of data into server responses. Please upgrade to React Router v7.14.0 or later.\n\n> [!NOTE]\n> This does not impact your React Router application if you are using [Declarative Mode](https://reactrouter.com/start/modes#declarative) (`<BrowserRouter>`) or [Data Mode](https://reactrouter.com/start/modes#data) (`createBrowserRouter`/`<RouterProvider>`).",
"summary": "React Router vulnerable to Denial of Service via reflected user input in single-fetch",
"affected": [
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "7.0.0"
},
{
"fixed": "7.14.0"
}
]
}
],
"package": {
"name": "react-router",
"ecosystem": "npm"
}
},
{
"ranges": [
{
"type": "ECOSYSTEM",
"events": [
{
"introduced": "0"
},
{
"fixed": "3.0.0"
}
]
}
],
"package": {
"name": "turbo-stream",
"ecosystem": "npm"
}
}
],
"modified": "2026-06-04T15:23:51Z",
"severity": [
{
"type": "CVSS_V3",
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
}
],
"published": "2026-06-04T15:23:51Z",
"references": [
{
"url": "https://github.com/remix-run/react-router/security/advisories/GHSA-rxv8-25v2-qmq8",
"type": "WEB"
},
{
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-34077",
"type": "ADVISORY"
},
{
"url": "https://github.com/remix-run/react-router/commit/59811921d3c7d599077b8cadccdcd65a233165e0",
"type": "WEB"
},
{
"url": "https://github.com/jacob-ebey/turbo-stream/blob/v2.4.1/src/flatten.ts#L175-L177",
"type": "WEB"
},
{
"url": "https://github.com/jacob-ebey/turbo-stream/blob/v2.4.1/src/unflatten.ts#L185-L189",
"type": "WEB"
},
{
"url": "https://github.com/remix-run/react-router",
"type": "PACKAGE"
}
],
"schema_version": "1.4.0",
"database_specific": {
"cwe_ids": [
"CWE-770"
],
"severity": "HIGH",
"github_reviewed": true,
"nvd_published_at": "2026-06-02T20:16:34Z",
"github_reviewed_at": "2026-06-04T15:23:51Z"
}
}