CVE-2025-29927

CRITICAL9.1EPSS 92.1%

Authorization Bypass in Next.js Middleware

Published: 3/21/2025Modified: 3/4/2026
Also known as:GHSA-f82v-jwr5-mffwCGA-fp7v-rgjp-xfjh

Description

# Impact It is possible to bypass authorization checks within a Next.js application, if the authorization check occurs in middleware. # Patches * For Next.js 15.x, this issue is fixed in `15.2.3` * For Next.js 14.x, this issue is fixed in `14.2.25` * For Next.js 13.x, this issue is fixed in 13.5.9 * For Next.js 12.x, this issue is fixed in 12.3.5 * For Next.js 11.x, consult the below workaround. _Note: Next.js deployments hosted on Vercel are automatically protected against this vulnerability._ # Workaround If patching to a safe version is infeasible, we recommend that you prevent external user requests which contain the `x-middleware-subrequest` header from reaching your Next.js application. ## Credits - Allam Rachid (zhero;) - Allam Yasser (inzo_)

Affected packages (1)

CVSS scores

SourceVersionSeverityVector
osvCVSS 3.1CRITICAL9.1CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

References (11)