CVE-2026-64642CWE-285

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

High · published July 27, 2026

CVSS v4.0
8.3
EPSS
1%
Percentile
49.8
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
8.3 · HIGH
Vector
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N
EPSS
0.00635 · 49.8th percentile
Weakness
CWE-285 · Improper Authorization
Published
2026-07-27T17:45Z
EPSS history
Timeline
  • 27 JUL 17:45Z
    Next.js: Middleware / Proxy bypass in App Router applications using Turbopack and single locale
    cvelistv5