Vulnerability · Published Jun 2, 2026 · Assigned by GitHub_M
CVE-2026-40181React Router's same-origin redirect with path starting // causes open redirect via protocol-relative URL reinterpretation
Medium 6.6
In plain English
A medium-severity open redirect in react-router from remix-run. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 13% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
React Router is a router for React. In versions 7.0.0 through 7.14.0 and 6.7.0 through 6.30.3, certain URLs passed to the redirect function can trigger an open redirect to an external domain due to path values starting with // being reinterpreted as protocol-relative URLs. The level of impact depends on the validation done by the application prior to returning the redirect. This does not impact applications using Declarative Mode (<BrowserRouter>). This is patched in versions 7.14.1 and 6.30.4.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| npm | @remix-run/router | 1.23.3 | GHSA-2j2x-hqr9-3h42 |
| npm | react-router | 7.14.1 | GHSA-2j2x-hqr9-3h42 |
| npm | react-router | 6.30.4 | GHSA-2j2x-hqr9-3h42 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| remix-run | react-router | >= 7.0.0, < 7.14.1>= 6.7.0, < 6.30.4 |
| remix-run | @remix-run/router | >= 1.3.0, < 1.23.3 |
Weakness: CWE-601 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U