CVE-2026-42211 PUBLISHED

React Router's vendored turbo-stream v2 allows arbitrary constructor invocation via TYPE_ERROR deserialization leading to Unauth RCE

Assigner: GitHub_M
Reserved: 25.04.2026 Published: 02.06.2026 Updated: 03.06.2026

React Router is a router for React. In versions 7.0.0 through 7.14.1, when using Framework Mode, a combination of steps could potentially allow unauthorized remote code execution (RCE) through external requests. This attack requires the application code to have an existing prototype pollution vulnerability, which can then be leveraged in a 2-step attack where the second step triggers unauthorized RCE on the remote server. This does not impact applications using Declarative Mode (<BrowserRouter>) or Data Mode (createBrowserRouter/<RouterProvider>). This is patched in version 7.14.2.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS Score: 8.1

Product Status

Vendor remix-run
Product react-router
Versions
  • Version >= 7.0.0, < 7.14.2 is affected

References

Problem Types

  • CWE-502: Deserialization of Untrusted Data CWE