Resource exhaustion in Remix-Run React-Router
CVE-2026-42342
React Router is a router for React. In versions 7.0.0 through 7.14.x of react-router and versions 2.10.0 through 2.17.4 of @remix-run/server-runtime, certain crafted requests can consume disproportionate server resources via unbounded path expansion in the __manifest endpoint, resulting in response time degradation and/or service unavailability for end users. This affects React Router Framework Mode applications as well as Remix applications. This does not impact applications using Declarative Mode (`<BrowserRouter>`) or Data Mode (`createBrowserRouter/<RouterProvider>`). This is patched in react-router version 7.15.0 and @remix-run/server-runtime version 2.17.5.
Vulnerability class: DoS (Denial of Service)
EPSS: 0.003 (22.4th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
Affected products
- Remix-run React-router — versions >= 7.0.0, < 7.15.0
- Remix-run @Remix-run/server-runtime — versions >= 2.10.0, < 2.17.5
- Shopify React-router
- Shopify Remix-run\/server-runtime
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-42342?
- CVE-2026-42342 is a high-severity vulnerability in Remix-Run React-Router, classified under Uncontrolled Resource Consumption. CVSS score: 7.5/10. Published 2026-06-02.
- How severe is CVE-2026-42342?
- High severity. CVSS v3 base score is 7.5 out of 10.