CVE-2026-64642

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

At a glance

Severity: HIGH 8.3
EPSS: EPSS 0.64 % · percentile 50 (2026-10-27)
State: PUBLISHED
Published: 2026-07-27
Updated: 2026-07-28
Assigner: GitHub_M
NVD status: Analyzed

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.

Scores

Version	Score	Vector	Scored by
CVSS 4.0	HIGH 8.3	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	GitHub_M
CVSS 4.0	HIGH 8.3	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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X	NVD · security-advisories@github.com (Secondary)
CVSS 3.1	HIGH 8.2	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N	NVD · nvd@nist.gov (Primary)

Weaknesses (CWE)

CWE-285

Advisories

GHSA-6gpp-xcg3-4w24 — Next.js: Middleware / Proxy bypass in App Router applications using Turbopack and single locale

European references

ENISA EUVD · EUVD-2026-49382
GCVE · GCVE-0-2026-64642

CERT-FR advisories

CERTFR-2026-AVI-1291 — Multiples vulnérabilités dans les produits IBM · cert.ssi.gouv.fr

Affected configurations (NVD CPE)

cpe:2.3:a:vercel:next.js:*:*:*:*:*:node.js:*:* ≥ 16.0.0 < 16.2.11

Affected products

Product	Versions
vercel · next.js	affected >= 16.0.0, < 16.2.11

References

Sources

Source	Licence
CVE List (CVEProject cvelistV5)	CVE Program Terms of Use
EPSS (FIRST.org)	FIRST — attribution requested
ENISA EUVD	ENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)	Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feeds	Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD