CVE-2026-55685: React Router: Unauthenticated Denial of Service via Inefficient Route Matching
Description
React Router is a router for React. In versions 7.0.0 through 7.17.0, the manifest endpoint could be accessed via unauthenticated targeted requests that would put heavy load on the server and slow down response times. This issue is a follow up to CVE-2026-42342, and does not does not impact React Router applications using Declarative Mode (<BrowserRouter>) or Data Mode (createBrowserRouter/<RouterProvider>). This issue has been fixed in version 7.18.0.
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H · CWE-400, CWE-407
Tracked companies
Mapped from the CVE’s affected-product data, NVD CPE matches, vendor advisories or package feeds. A mapping means the vendor’s software is named, not that its hosted service was exposed.
Status incidents that name it
No tracked status incident names this CVE.
Affected vendors and products
remix-run: react-router
References
- CVE record on cve.org (opens in new tab)
- NVD entry (opens in new tab)
- github.com/remix-run/react-router/blob/main/CHANGELOG.md (opens in new tab)
- github.com/remix-run/react-router/commit/09e6020d1950e54f361f7ad00938ecd4dde6092… (opens in new tab)
- github.com/remix-run/react-router/pull/15186 (opens in new tab)
- github.com/remix-run/react-router/releases/tag/react-router@7.18.0 (opens in new tab)
- github.com/remix-run/react-router/security/advisories/GHSA-8x6r-g9mw-2r78 (opens in new tab)
- github.com/remix-run/react-router/security/advisories/GHSA-chx6-hx7r-mcp5 (opens in new tab)
- CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (opens in new tab)
- This product uses data from the NVD API but is not endorsed or certified by the NVD. (opens in new tab)
- Known Exploited Vulnerabilities catalog from CISA. (opens in new tab)
- EPSS scores from FIRST (Exploit Prediction Scoring System). (opens in new tab)