Vulnerability Report

CVE-2026-44573

Title: Pages Router i18n Authorization Bypass

Auth Bypass

Proof Of Concept

No public PoC currently indexed for CVE-2026-44573.

CWE Category CWE-863

Published Date May 13, 2026

Modified Date May 14, 2026

Exploit Status Not Found

Score 7.5 CVSS v3.1

Exploit Probability (EPSS)

0.05%

Vulnerability Summary

CVE-2026-44573: 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.

Impacted Vendors

vercel 1

kanopi 1

Reference Links

https://github.com/vercel/next.js/security/advisories/GHSA-36qx-fr4f-26g5

CVSS v3.1

Source Entity [email protected]

Severity HIGH

7.5

Attack Vector

NETWORK

Complexity

LOW

Privileges

N/A

Interaction

NONE

Confidentiality

N/A

Integrity

N/A

Availability

N/A

Scope

UNCHANGED

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

Associated Attack Patterns (CAPEC)

Total: Patterns

CVE-2026-44573 Exploits & PoCs (Proof Of Concept)

No public PoCs found in our database for this CVE.

May 14, 2026 MODIFIED

Vulnerability data updated via NVD.

May 13, 2026 MODIFIED

Vulnerability data updated via NVD.

Attack Vector Matrix

Access Vector NETWORK

Complexity LOW

Privileges N/A

Interaction NONE

CVSS Vector String


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

Affected Stack

No specific products linked.