GHSA-qwww-vcr4-c8h2
React Router: RSC Mode CSRF Bypass Allows Action Execution Before 400 Response
- Severity
- 7.1 / 10
- High · CVSS 4.0
- Exploit chance (EPSS)
- —
- No score published
- Known exploited
- No
- Not in CISA's catalog
- Weakness
- CWE-352 Cross-Site Request Forgery (CSRF)
- Fix
7.18.2- Upgrade react-router to this version or later
Description
This is a follow up to CVE-2026-22030 to address related CSRF flows in unstable RSC code paths.
[!NOTE] This only affects your application if you are using the unstable RSC APIs
Affected versions
npm
| Package | Vulnerable | Fixed in |
|---|---|---|
| react-router | >= 7.12.0, < 7.18.2 |
7.18.2 |
| react-router | >= 8.0.0, < 8.3.0 |
8.3.0 |
| react-router | >= 7.12.0, < 7.18.2 |
7.18.2 |
| react-router | >= 8.0.0, < 8.3.0 |
8.3.0 |
How to fix
Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.
react-router npm → 7.18.2
- npm
npm install react-router@7.18.2- yarn
yarn add react-router@7.18.2- pnpm
pnpm add react-router@7.18.2
Severity breakdown
CVSS 4.0 7.1
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
- Attack vector
- Network
- Attack complexity
- Low
- Attack requirements
- None
- Privileges required
- None
- User interaction
- Passive
- Confidentiality (vulnerable system)
- None
- Integrity (vulnerable system)
- High
- Availability (vulnerable system)
- None
- Confidentiality (subsequent systems)
- None
- Integrity (subsequent systems)
- None
- Availability (subsequent systems)
- None
Weakness
CWE-352: Cross-Site Request Forgery (CSRF)
The web application does not, or cannot, sufficiently verify whether a request was intentionally provided by the user who sent the request, which could have originated from an unauthorized actor.
How to prevent it
- Architecture and Design: Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid [REF-1482]. For example, use anti-CSRF packages such as the OWASP CSRFGuard. [REF-330] Another example is the ESAPI Session Management control, which includes a component for CSRF. [REF-45]
- Implementation: Ensure that the application is free of cross-site scripting issues (CWE-79), because most CSRF defenses can be bypassed using attacker-controlled script.
- Architecture and Design: Generate a unique nonce for each form, place the nonce into the form, and verify the nonce upon receipt of the form. Be sure that the nonce is not predictable (CWE-330). [REF-332]
- Architecture and Design: Identify especially dangerous operations. When the user performs a dangerous operation, send a separate confirmation request to ensure that the user intended to perform that operation.
- Architecture and Design: Use the "double-submitted cookie" method as described by Felten and Zeller: When a user visits a site, the site should generate a pseudorandom value and set it as a cookie on the user's machine. The site should require every form submission to include this value as a form value and also as a cookie value. When a POST request is sent to the site, the request should only be considered valid if the form value and the cookie value are the same. Because of the same-origin policy, an attacker cannot read or modify the value stored in the cookie. To successfully submit a form on behalf of the user, the attacker would have to correctly guess the pseudorandom value. If the pseudorandom value is cryptographically strong, this will be prohibitively difficult. This technique requires Javascript, so it may not work for browsers that have Javascript disabled. [REF-331]
- Architecture and Design: Do not use the GET method for any request that triggers a state change.
- Implementation: Check the HTTP Referer header to see if the request originated from an expected page. This could break legitimate functionality, because users or proxies may have disabled sending the Referer for privacy reasons.
References
Advisories
Fixes and patches
Packages
Other links
Timeline
- Published
- Last updated by the source
Related advisories
| Advisory | Severity | Why it's related |
|---|---|---|
| GHSA-chx6-hx7r-mcp5 React Router: Unauthenticated Denial of Service via Inefficient Route Matching | High | Also affects react-router |
| GHSA-wrjc-x8rr-h8h6 React Router: Open redirect via backslash in <Link> and useNavigate (CVE-2025-68470 bypass) | Medium | Also affects react-router |
| GHSA-jjmj-jmhj-qwj2 React Router: Open redirect leading to XSS | Medium | Also affects react-router |
| GHSA-h8fp-f39c-q6mh React Router: RSCErrorHandler Missing Protocol Validation (XSS) | Medium | Also affects react-router |
| GHSA-337j-9hxr-rhxg React Router: Arbitrary Constructor Injection via deserializeErrors() in React Router SSR Hydration | Medium | Also affects react-router |
| GHSA-84g9-w2xq-vcv6 React Router: Potential CSRF via PUT/PATCH/DELETE document requests | Low | Also affects react-router |
| GHSA-8x6r-g9mw-2r78 React Router vulnerable to DoS via unbounded path expansion in __manifest endpoint | High | Also affects react-router |
| GHSA-49rj-9fvp-4h2h React Router's vendored turbo-stream v2 allows arbitrary constructor invocation via TYPE_ERROR deserialization leading to Unauth RCE | High | Also affects react-router |
Credits: AlexGustafsson, Jojo134, KsAkira10, acastlesibm, benfranke, bosnian, erkro1, georgevgs, giladmoyal-ai, grgrzybek, jochenschmich-aeberle, marshalium, omgovich, radityahack, ryanthemanuel, yhlee-tw
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