Medium severity · published Jun 2, 2026
CVE-2026-33244
React Router has stored XSS via unescaped Location header in prerendered redirect HTML
5.4
CVSS
0.1%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.1% · higher than 4% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
RE
react-router · remix-run
>= 7.5.1, < 7.13.2 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-33244
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-33244
Vendor Advisory
https://github.com/remix-run/react-router/security/advisories/GHSA-f22v-gfqf-p8f3
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