CVE-2026-42342: CWE-400: Uncontrolled Resource Consumption in remix-run react-router
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.
AI Analysis
Technical Summary
React Router and @remix-run/server-runtime contain a vulnerability (CWE-400) where crafted requests to the __manifest endpoint trigger unbounded path expansion, leading to excessive server resource consumption. This results in degraded response times or potential denial of service for affected applications using Framework Mode. The vulnerability affects react-router versions from 7.0.0 up to but not including 7.15.0 and @remix-run/server-runtime versions 2.10.0 through 2.17.4. Applications using Declarative Mode or Data Mode are not impacted. The issue is addressed by updating to react-router 7.15.0 or @remix-run/server-runtime 2.17.5.
Potential Impact
The vulnerability can cause significant degradation of service or unavailability due to excessive resource consumption triggered by maliciously crafted requests. It does not impact confidentiality or integrity but affects availability (CVSS impact: A:H). No known active exploitation has been reported.
Mitigation Recommendations
A fix is available by upgrading react-router to version 7.15.0 or later and @remix-run/server-runtime to version 2.17.5 or later. Users should apply these updates to remediate the vulnerability. No additional vendor advisory content is provided, so patch status is based on the version information in the description.
CVE-2026-42342: CWE-400: Uncontrolled Resource Consumption in remix-run react-router
Description
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.
CVSS v3.1
Score 7.5high
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
React Router and @remix-run/server-runtime contain a vulnerability (CWE-400) where crafted requests to the __manifest endpoint trigger unbounded path expansion, leading to excessive server resource consumption. This results in degraded response times or potential denial of service for affected applications using Framework Mode. The vulnerability affects react-router versions from 7.0.0 up to but not including 7.15.0 and @remix-run/server-runtime versions 2.10.0 through 2.17.4. Applications using Declarative Mode or Data Mode are not impacted. The issue is addressed by updating to react-router 7.15.0 or @remix-run/server-runtime 2.17.5.
Potential Impact
The vulnerability can cause significant degradation of service or unavailability due to excessive resource consumption triggered by maliciously crafted requests. It does not impact confidentiality or integrity but affects availability (CVSS impact: A:H). No known active exploitation has been reported.
Mitigation Recommendations
A fix is available by upgrading react-router to version 7.15.0 or later and @remix-run/server-runtime to version 2.17.5 or later. Users should apply these updates to remediate the vulnerability. No additional vendor advisory content is provided, so patch status is based on the version information in the description.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-04-26T13:26:14.514Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a1f3494e29bf47b50fa2524
Added to database: 6/2/2026, 7:52:52 PM
Last enriched: 6/2/2026, 8:03:49 PM
Last updated: 6/3/2026, 5:08:37 AM
Views: 7
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