CVE-2026-21884: Shopify React-Router

High severity, CVSS 8.2. EPSS: 0.5% chance of exploitation in the next 30 days.

React Router is a router for React. In @remix-run/react version prior to 2.17.3. and react-router 7.0.0 through 7.11.0, a XSS vulnerability exists in in React Router's <ScrollRestoration> API in Framework Mode when using the getKey/storageKey props during Server-Side Rendering which could allow arbitrary JavaScript execution during SSR if untrusted content is used to generate the keys. There is no impact if server-side rendering in Framework Mode is disabled, or if Declarative Mode (<BrowserRouter>) or Data Mode (createBrowserRouter/<RouterProvider>) is being used. This issue has been patched in @remix-run/react version 2.17.3 and react-router version 7.12.0.

Affected products

• Shopify React-Router: from 7.0.0, up to and including 7.11.0
• Shopify Remix-Run/react: before 2.17.3 (fixed in 2.17.3)

Published 2026-01-10. Last modified 2026-07-15.