---
id: CVE-2026-44573
title: Next.js is a React framework for building full-stack web applications
summary: >-
  Next.js is a React framework for building full-stack web applications. From
  12.2.0 to before 15.5.16 and 16.2.5, Applications using the Pages Router with
  i18n configured and middleware/proxy-based authorization can allow
  unauthorized acc…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N'
cwe:
  - CWE-863
  - CWE-551
vendor: vercel
product: next.js
affected:
  - 'next.js >= 12.2.0, < 15.5.16'
  - 'next.js >= 16.0.0, < 16.2.5'
patched:
  - next.js 16.2.5
published: '2026-05-13'
updated: '2026-07-03'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-44573'
references:
  - url: 'https://github.com/vercel/next.js/security/advisories/GHSA-36qx-fr4f-26g5'
    label: security-advisories@github.com
  - url: 'https://access.redhat.com/errata/RHSA-2026:34608'
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
  - url: 'https://access.redhat.com/security/cve/CVE-2026-44573'
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2477199'
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-44573.json
    label: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
tags:
  - nvd
epss: 0.0062
epssPercentile: 0.48045
ingestedAt: '2026-07-03T14:03:37.040Z'
---

## Overview

Next.js is a React framework for building full-stack web applications. From 12.2.0 to before 15.5.16 and 16.2.5, Applications using the Pages Router with i18n configured and middleware/proxy-based authorization can allow unauthorized access to protected page data through locale-less /_next/data/<buildId>/<page>.json requests. In affected configurations, middleware does not run for the unprefixed data route, allowing an attacker to retrieve SSR JSON for protected pages without passing the intended authorization checks. This vulnerability is fixed in 15.5.16 and 16.2.5.

## Affected

- `next.js >= 12.2.0, < 15.5.16`
- `next.js >= 16.0.0, < 16.2.5`

## Remediation

Upgrade past the affected range:

- `next.js 16.2.5`