What’s Vulnerable › Vulnerabilities
CVE-2026-34077: React Router vulnerable to Denial of Service via reflected user input in single-fetch
- Severity: high (CVSS 7.5 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.3% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-06-02 · updated 2026-07-22
- Weakness: CWE-770
Description
React Router is a router for React. In versions 7.7.0 through 7.13.1, when using React Router's unstable React Server Components (RSC) APIs, there is a potential client-side Cross-Site Scripting (XSS) vulnerability in the RSC redirect handling if redirects come from untrusted sources. This does not impact applications that are not using the unstable RSC APIs in React Router. This is patched in version 7.13.2.
Affected products
- remix-run react-router: from 7.0.0 before 7.14.0 — fixed in 7.14.0
- Turbo-Stream Turbo Stream: before 3.0.0 — fixed in 3.0.0
How to fix
Upgrade to a fixed version: remix-run react-router 7.14.0; Turbo-Stream Turbo Stream 3.0.0. Check the vendor advisory for mitigations.
References
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