CVE-2026-40181
mediumpriority · track · 24EPSS 0.002 · 12 %ileDEEURUUSEPSS · scored 2026-10-22
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (13)
Products and version ranges known to be affected.
advisories (2)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2026-3046IBM Concert: Mehrere SchwachstellenDeutsch2026-08-26csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in IBM Concert ausnutzen, um beliebigen Programmcode auszuführen, um einen Denial of Service Angriff durchzuführen, um Informationen offenzulegen, um Dateien zu manipulieren, um einen Cross-Site Scripting Angriff durchzuführen, um einen SQL-Injection Angriff durchzuführen und um Sicherheitsvorkehrungen zu umgehen.
- GHSA-2j2x-hqr9-3h42React Router's same-origin redirect with path starting // causes open redirect via protocol-relative URL reinterpretation2026-06-03ghsa · osvUS
Certain URLs passed to the `redirect` function can trigger an open redirect to an external domain depending on the level of validation done by the application prior to returning the `redirect`. > [!NOTE] > This does not impact your React Router application if you are using [Declarative Mode](https://reactrouter.com/start/modes#declarative) (`<BrowserRouter>`)
also known as (4)
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sources
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references (4)
External citations — patches, advisories, analysis.
- https://github.com/remix-run/react-router/releasesPatchcnnvd
- https://github.com/remix-run/react-router/security/advisories/GHSA-2j2x-hqr9-3h42cnnvd
- https://github.com/remix-run/react-router/security/advisories/GHSA-2j2x-hqr9-3h42enisa_euvd
- https://github.com/remix-run/react-router/security/advisories/GHSA-2j2x-hqr9-3h42Vendor Advisorynvd
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