Stored Cross-Site Scripting Vulnerability in Next.js Framework by Vercel
CVE-2026-44581

4.7MEDIUM

Key Information:

Vendor

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

What is CVE-2026-44581?

Next.js, a popular React framework for building full-stack web applications, is susceptible to stored cross-site scripting in certain versions. When deployed behind shared caches, applications relying on Content Security Policy (CSP) nonces can experience this vulnerability. Malformed nonce values originating from request headers may be improperly reflected into the rendered HTML, which enables potential attackers to poison cached responses. This leads to script execution when future visitors access the affected content. The vulnerability is addressed in Next.js versions 15.5.16 and 16.2.5.

Affected Version(s)

next.js >= 13.4.0, < 15.5.16 < 13.4.0, 15.5.16

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

References

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

CVSS V3.1

Score:
4.7
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
Low
Availability:
Low
Attack Vector:
Network
Attack Complexity:
High
Privileges Required:
None
User Interaction:
Required
Scope:
Changed

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.