CVE-2026-34077: high-severity vulnerability in remix-run react-router
React Router vulnerable to Denial of Service via reflected user input in single-fetch
Published · Updated
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.5epss 0.3%
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Related CVEs — remix-run react-router
In the same product, most dangerous first.
CVE-2025-43864HIGHReact Router allows a DoS via cache poisoning by forcing SPA modeEPSS 20.5%CVE-2025-61686CRITICALReact Router has Path Traversal in File Session StorageEPSS 17.3%CVE-2025-31137HIGHRemix and React Router allow URL manipulation via Host / X-Forwarded-Host headersEPSS 1.2%CVE-2026-22029HIGHReact Router vulnerable to XSS via Open RedirectsEPSS 0.9%CVE-2025-43865HIGHReact Router allows pre-render data spoofing on React-Router framework modeEPSS 0.8%CVE-2026-55685HIGHReact Router: Unauthenticated Denial of Service via Inefficient Route MatchingEPSS 0.7%