CVE-2026-42342

React Router vulnerable to DoS via unbounded path expansion in __manifest endpoint

CVSS 3.1 7.5 HIGHEUVD CVSS 3.1 7.5 CVSS 3.1 · [email protected] · Secondary 7.5 HIGHCVSS_V3 Publisher rating HIGHFixed by react-router 7.15.0 Fixed by @remix-run/server-runtime 2.17.5KEV status unknown

Original advisory

cve-program · CVE-2026-42342

Published

React Router is a router for React. In versions 7.0.0 through 7.14.x of react-router and versions 2.10.0 through 2.17.4 of @remix-run/server-runtime, certain crafted requests can consume disproportionate server resources via unbounded path expansion in the __manifest endpoint, resulting in response time degradation and/or service unavailability for end users. This affects React Router Framework Mode applications as well as Remix applications. This does not impact applications using Declarative Mode (`<BrowserRouter>`) or Data Mode (`createBrowserRouter/<RouterProvider>`). This is patched in react-router version 7.15.0 and @remix-run/server-runtime version 2.17.5.

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euvd · EUVD-2026-34000

Published

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nvd · CVE-2026-42342

Published

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osv · GHSA-8x6r-g9mw-2r78

Published

There exists a potential DOS attack vector in React Router Framework Mode applications (as well as Remix v2.10.0 - 2.17.4). Certain requests can be crafted to consume disproportionate resources on the server, resulting in response time degredation and/or service unavailability for end users. > [!NOTE] > 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>`).

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Affected versions, risk and source history

Exploitation and risk

Source status

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Risk history

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Advisory history

13 saved versions

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15 Nov 2026 13:05:26 UTC