Is This vulnerability exploited in the wild?

No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.

How severe is This vulnerability?

Medium severity, with a CVSS score of 4, published 24 July 2026.

Which products and versions are affected?

React-Router SEMVER:introduced=7.12.0,fixed=7.18.2.

Is there a fix for This vulnerability?

Yes. React-Router: upgrade to 7.18.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is This vulnerability attacked?

It is attacked over the network.

Check whether you run React-Router at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

React Router CSRF bypass in RSC mode

Severity: medium · CVSS 4 · Published 2026-07-24

React Router is a JavaScript routing library used to build single-page applications. The RSC (React Server Components) mode includes a CSRF protection mechanism that can be bypassed, allowing an attacker to execute server actions without proper token validation. This could lead to unauthorized state changes or data modification on affected applications using unstable RSC APIs.

Technologies: React-Router.

Quick answers

Is This vulnerability exploited in the wild?: No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.
How severe is This vulnerability?: Medium severity, with a CVSS score of 4, published 24 July 2026.
Which products and versions are affected?: React-Router SEMVER:introduced=7.12.0,fixed=7.18.2.
Is there a fix for This vulnerability?: Yes. React-Router: upgrade to 7.18.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is This vulnerability attacked?: It is attacked over the network.
Am I affected?: Check whether you run React-Router at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

React-Router: upgrade to 7.18.2 or later

Technical details

This vulnerability is a CSRF bypass (CWE-352) in React Router's unstable RSC code paths. The vulnerability allows server actions to be executed before a 400 response is returned, bypassing CSRF protections in place. The issue requires user interaction (e.g., a user visiting a malicious site) and only affects applications using the unstable RSC APIs. An attacker can craft a cross-site request to trigger unintended server actions with the victim's credentials. Patches are available in versions 7.18.2 and 8.3.0.

Affected products

Remix React Router 7.12.0 to 7.18.1, 8.0.0 to 8.2.x

Timeline

2026-07-24: disclosed
2026-07-28: patched: Patches released in versions 7.18.2 and 8.3.0

References

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