Acceptance of Extraneous Untrusted Data With Trusted Data in Next.js - CVE-2026-44572
Published: May 6, 2026
Vulnerability identifier: #VU130282
CSH Severity: Low
CVSS v4: 6.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-44572
CWE-ID: CWE-349
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to acceptance of extraneous untrusted data with trusted data in middleware / proxy redirect handling when processing a normal request with a spoofed x-nextjs-data header on a path that returns a redirect. A remote attacker can send a specially crafted request to cause a denial of service.
Exploitation requires the application to be deployed behind a caching CDN or reverse proxy that caches 3xx responses for the affected path without varying on the x-nextjs-data header.
Affected software
Next.js
How to mitigate CVE-2026-44572
Install security update from vendor's website.
Next.js - addressed in versions 15.5.16, 16.2.5