vercel next.js up to 15.5.15/16.2.4 cross site scripting

Summaryinfo

A vulnerability was found in vercel next.js up to 15.5.15/16.2.4 and classified as problematic. This vulnerability affects unknown code. The manipulation results in cross site scripting. This vulnerability is identified as CVE-2026-44581. The attack can be executed remotely. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in vercel next.js up to 15.5.15/16.2.4. It has been classified as problematic. Affected is an unknown code. The manipulation with an unknown input leads to a cross site scripting vulnerability. CWE is classifying the issue as CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. This is going to have an impact on integrity. CVE summarizes:

Next.js is a React framework for building full-stack web applications. From 13.4.0 to before 15.5.16 and 16.2.5, App Router applications that rely on CSP nonces can be vulnerable to stored cross-site scripting when deployed behind shared caches. In affected versions, malformed nonce values derived from request headers could be reflected into rendered HTML in an unsafe way, allowing an attacker to poison cached responses and cause script execution for later visitors. This vulnerability is fixed in 15.5.16 and 16.2.5.

The advisory is shared for download at github.com. This vulnerability is traded as CVE-2026-44581 since 05/06/2026. The exploitability is told to be difficult. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1059.007.

The vulnerability scanner Nessus provides a plugin with the ID 314907 (Next.js Framework 13.4.x < 15.5.16 / 16.x < 16.2.5 Stored XSS), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 15.5.16 or 16.2.5 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (314907) and CERT Bund (WID-SEC-2026-1401). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

• Vercel Next.js

Productinfo

Type

• JavaScript Library

Vendor

• vercel

Name

• next.js

Version

• 15.5.0
• 15.5.1
• 15.5.2
• 15.5.3
• 15.5.4
• 15.5.5
• 15.5.6
• 15.5.7
• 15.5.8
• 15.5.9
• 15.5.10
• 15.5.11
• 15.5.12
• 15.5.13
• 15.5.14
• 15.5.15
• 16.2.0
• 16.2.1
• 16.2.2
• 16.2.3
• 16.2.4

Website

• Product: https://github.com/vercel/next.js/

CPE 2.3info

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CPE 2.2info

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Entryinfo

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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