High

React Router: Unauthenticated Denial of Service via Inefficient Route Matching

  • Disclosed: 24.07.2026
  • Updated: 11.10.2026 10:22

This is a follow up to https://github.com/remix-run/react-router/security/advisories/GHSA-8x6r-g9mw-2r78 that covers additional reported scenarios in which the manifest endpoint could be accessed via unauthenticated targeted requests that would put heavy load on the server and slow down response times.

[!NOTE] This only impacts Framework Mode applications. This does not impact your application if you are using Declarative or Data Mode.

Affected software

Click a technology to see all vulnerabilities affecting it.

PlatformPackageVulnerable versionsFixed in
npm package react-router >= 7.0.0, < 7.18.0 7.18.0

References

CVSS score -
CVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Weakness (CWE)
CWE-400, CWE-407
Platform
npm
Package
react-router
Disclosed
24.07.2026
Updated
11.10.2026 10:22

Sources and licenses

OSV / GitHub Advisory Database - GHSA-chx6-hx7r-mcp5 - CC BY 4.0

Vulnerability history: react-router

All published vulnerabilities of this package (npm package), newest first. Shows whether this is a one-off slip or a package that needs watching.

All (20) in the archive
Total entries
20
First → latest
04.2025 07.2026
Without a fix
0
Exploited in attacks
0

Severity breakdown

  • High 11
  • Medium 8
  • Low 1

Disclosures per year

  1. 2025: 2
  2. 2026: 18
Severity:
  1. High ghsa-qwww-vcr4-c8h2 >= 7.12.0, < 7.18.2, >= 8.0.0, < 8.3.0 7.18.2, 8.3.0
  2. React Router: Unauthenticated Denial of Service via Inefficient Route Matching this entry
    High CVE-2026-55685 >= 7.0.0, < 7.18.0 7.18.0
  3. High · 7.5 CVE-2026-42342 >= 7.0.0, < 7.15.0 7.15.0
  4. High · 8.0 CVE-2026-22029 >= 7.0.0, < 7.12.0 7.12.0
  5. High · 8.2 CVE-2026-21884 >= 7.0.0, < 7.12.0 7.12.0
  6. High · 7.6 CVE-2025-59057 >= 7.0.0, < 7.9.0 7.9.0
  7. High · 8.2 CVE-2025-43865 >= 7.0.0-pre.0, < 7.5.2 7.5.2
  8. High · 7.5 CVE-2025-43864 >= 7.2.0, < 7.5.2 7.5.2

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