CVE-2026-45109 HIGH

CVE-2026-45109: Next.js: Middleware / Proxy bypass in App Router applications via segment-prefetch routes

Vendor Vercel
Product next.js
Weakness CWE-288
Published May 13, 2026
Last update June 30, 2026
View on NVD All CVEs

CVSS base score

7.5/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality High
Integrity None

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

What the vulnerability does

01Description

Next.js is a React framework for building full-stack web applications. From 15.2.0 to before 15.5.18 and 16.2.6, it was found that the fix addressing CVE-2026-44575 did not apply to middleware.ts with Turbopack. This vulnerability is fixed in 15.5.18 and 16.2.6.

Key dates

02Disclosure timeline

May 13, 2026 CVE published
June 30, 2026 Record updated