CVE-2026-64642Next.js: Middleware / Proxy bypass in App Router applications using Turbopack and single locale

Description

Next.js is a React framework for building full-stack web applications. In versions 16.0.0 through 16.2.10, crafted requests targeting Next.js applications using App Router built with Turbopack and a single entry in config.i18n.locales can bypass middleware/proxy based authentication. This issue has been fixed in version 16.2.11.

Data: CVE.org, NVD, CISA KEV, FIRST EPSS, Ubuntu. Published as the sources state it, in English.

Affected products and versions

References and patches

• https://github.com/vercel/next.js/security/advisories/GHSA-6gpp-xcg3-4w24 Vendor Advisory
• https://github.com/vercel/next.js/pull/96014 Issue TrackingPatch
• https://github.com/vercel/next.js/commit/6bf4df14508ad6c0cd46af50c6051ee42f2d9151 Patch
• https://github.com/vercel/next.js/releases/tag/v16.2.11 ProductRelease Notes