Vulnerability · Published Jun 2, 2026 · Assigned by GitHub_M

CVE-2026-33244React Router has stored XSS via unescaped Location header in prerendered redirect HTML

Medium 5.4

In plain English

A medium-severity cross-site scripting in react-router from remix-run. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 4% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)5.4Medium

Exploit odds (30 days)0.1%top 96.2% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official 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 packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
npm	react-router	7.13.2	GHSA-f22v-gfqf-p8f3

Affected products (as reported)

Vendor	Product	Versions
remix-run	react-router	>= 7.5.1, < 7.13.2

Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

References

https://github.com/remix-run/react-router/security/advisories/GHSA-f22v-gfqf-p8f3 x_refsource_CONFIRM