CVE-2026-44574

Next.js: Middleware / Proxy bypass through dynamic route parameter injection

Published May 13, 2026 CVSS 3.1 · 8.1 High EPSS < 1% KEV · Not listed
Description
Next.js is a React framework for building full-stack web applications. From 15.4.0 to before 15.5.16 and 16.2.5, applications that rely on middleware to protect dynamic routes can be vulnerable to authorization bypass. In affected deployments, specially crafted query parameters can alter the dynamic route value seen by the page while leaving the visible path unchanged, which can allow protected content to be rendered without passing the expected middleware check. This vulnerability is fixed in 15.5.16 and 16.2.5.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-492v-c6pp-mqqv Next.js has a Middleware / Proxy bypass through dynamic route parameter injection
History
Type Values Removed Values Added
CPEs cpe:2.3:a:vercel:next.js:*:*:*:*:*:node.js:*:*
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Vercel
Vercel next.js
Vendors & Products Vercel
Vercel next.js
Type Values Removed Values Added
Description Next.js is a React framework for building full-stack web applications. From 15.4.0 to before 15.5.16 and 16.2.5, applications that rely on middleware to protect dynamic routes can be vulnerable to authorization bypass. In affected deployments, specially crafted query parameters can alter the dynamic route value seen by the page while leaving the visible path unchanged, which can allow protected content to be rendered without passing the expected middleware check. This vulnerability is fixed in 15.5.16 and 16.2.5.
Title Next.js: Middleware / Proxy bypass through dynamic route parameter injection
Weaknesses CWE-288
References
Metrics cvssV3_1

{'score': 8.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Aug 13, 2026, 12:04 PM
Reserved
May 6, 2026, 9:49 PM
Status
Modified
Published
May 13, 2026, 5:16 PM
Modified
Oct 26, 2026, 5:10 PM
Severity
Important
Public date
May 13, 2026, 4:56 PM