What’s Vulnerable › Vulnerabilities
CVE-2026-33244: React Router has stored XSS via unescaped Location header in prerendered redirect HTML
- Severity: medium (CVSS 5.4 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.1% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-06-02 · updated 2026-07-21
- Weakness: CWE-79
Description
React Router is a router for React. In versions 7.5.1 through 7.13.1, when using Framework Mode with pre-rendering enabled, improper neutralization of the HTTP `Location` header value can permit Cross-Site Scripting (XSS) in the statically generated HTML files if the redirect location comes from an untrusted source. This does not impact applications using Declarative Mode (`<BrowserRouter>`) or Data Mode (`createBrowserRouter/<RouterProvider>`). This is patched in version 7.13.2.
Affected products
- remix-run react-router: from 7.5.1 before 7.13.2 — fixed in 7.13.2
How to fix
Upgrade to a fixed version: remix-run react-router 7.13.2. Check the vendor advisory for mitigations.
References
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