HighGHSA-6gpp-xcg3-4w24CVE-2026-64642
Next.js: Middleware / Proxy bypass in App Router applications using Turbopack and single locale
Published 22 Jul 2026 · Updated 10 Sept 2026
Affected package
nextnpm
- Affected
- >=16.0.0 <16.2.11
- Fixed in
- 16.2.11
Update to the fixed version for your release line, for example:
npm install next@16.2.11Details
Impact
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.
Workarounds
If you cannot upgrade immediately, enforce authorization in the page's server-side data path instead of relying solely on middleware.
Is GHSA-6gpp-xcg3-4w24 in any of your client repos?
Checking one package by hand is fine. Checking it across forty client projects is not. NPMscan reads the lockfiles in every GitHub repo you pick, finds each project with an affected next, and gives you the command that fixes it.
References
Advisory data from OSV.dev (opens OSV.dev in a new tab), refreshed daily.