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
This vulnerability (CVE-2026-42342) in react-router and @remix-run/server-runtime allows crafted requests to trigger unbounded path expansion in the __manifest endpoint, leading to excessive server resource consumption. This results in degraded response times or denial of service conditions for affected applications using React Router Framework Mode or Remix. Applications using Declarative Mode (<BrowserRouter>) or Data Mode (createBrowserRouter/<RouterProvider>) are not impacted. The vulnerability is fixed in react-router version 7.15.0 and @remix-run/server-runtime version 2.17.5.
Potential Impact
Exploitation of this vulnerability can cause high resource consumption on the server, leading to degraded response times or service unavailability for end users. There is no impact on confidentiality or integrity, only availability is affected.
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 other mitigations are specified.
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
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-42342) in react-router and @remix-run/server-runtime allows crafted requests to trigger unbounded path expansion in the __manifest endpoint, leading to excessive server resource consumption. This results in degraded response times or denial of service conditions for affected applications using React Router Framework Mode or Remix. Applications using Declarative Mode (<BrowserRouter>) or Data Mode (createBrowserRouter/<RouterProvider>) are not impacted. The vulnerability is fixed in react-router version 7.15.0 and @remix-run/server-runtime version 2.17.5.
Potential Impact
Exploitation of this vulnerability can cause high resource consumption on the server, leading to degraded response times or service unavailability for end users. There is no impact on confidentiality or integrity, only availability is affected.
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 other mitigations are specified.
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: 06/02/2026, 19:52:52 UTC
Last enriched: 06/10/2026, 11:15:56 UTC
Last updated: 07/31/2026, 19:22:58 UTC
Views: 59
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