CVE-2026-44572

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, an external client could send a x-nextjs-data header on a normal request to a path handled by middleware that returns a redirect. When that happened, the middleware/proxy could treat the request as a data request and replace the standard Location redirect header with the internal x-nextjs-redirect header. Browsers do not follow x-nextjs-redirect, so the response became an unusable redirect for normal clients. If the application was deployed behind a CDN or reverse proxy that caches 3xx responses without varying on this header, a single attacker request could poison the cached redirect response for the affected path. Subsequent visitors could then receive a cached redirect response without a Location header, causing a denial of service for that redirect path until the cache entry expired or was purged. This vulnerability is fixed in 15.5.16 and 16.2.5.

CVSS v3 3.7 LOW

3.7^/10

CVSS v3 : LOW

Vector :

Exploitability : 2.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/vercel/next.js/security/advisories/GHSA-3g8h-86w9-wvmq	Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:vercel:next.js::::::node.js::*
	cpe:2.3:a:vercel:next.js::::::node.js::*

History

15 May 2026, 15:46

Type	Values Removed	Values Added
References	~~() https://github.com/vercel/next.js/security/advisories/GHSA-3g8h-86w9-wvmq -~~	() https://github.com/vercel/next.js/security/advisories/GHSA-3g8h-86w9-wvmq - Mitigation, Vendor Advisory
CPE		cpe:2.3:a:vercel:next.js::::::node.js::*
First Time		Vercel next.js Vercel

13 May 2026, 16:58

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-13 16:16

Updated : 2026-05-15 15:46

NVD link : CVE-2026-44572

Mitre link : CVE-2026-44572

CVE.ORG link : CVE-2026-44572

JSON object : View

Products Affected

vercel

next.js

CWE

CWE-349

Acceptance of Extraneous Untrusted Data With Trusted Data

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