Authorization Bypass in Next.js Framework by Vercel
CVE-2026-44575

7.5HIGH

Key Information:

Vendor

Vercel
Status
Next.js
Vendor
CVE Published:
13 May 2026

What is CVE-2026-44575?

Next.js, a popular React framework for building full-stack web applications, has a vulnerability that can be exploited in App Router applications using middleware or proxy-based authorization checks. Affected versions from 15.2.0 to prior to 15.5.16 and 16.2.5 allow specially crafted request URLs, specifically .rsc and segment-prefetch URLs, to access protected content without passing the required authorization checks. This flaw can lead to unauthorized access to sensitive information. The issue has been addressed in versions 15.5.16 and 16.2.5.

Affected Version(s)

next.js >= 16.0.0, < 16.2.5 < 16.0.0, 16.2.5

next.js >= 15.2.0, < 15.5.16 < 15.2.0, 15.5.16

References

https://github.com/vercel/next.js/security/advisories/GHS...
x_refsource_CONFIRM

CVSS V3.1

Score:
7.5
Severity:
HIGH
Confidentiality:
High
Integrity:
None
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.