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. It has been classified as problematic. Affected by this issue is some unknown functionality. The manipulation leads to cross site scripting. This vulnerability is listed as CVE-2026-44580. The attack may be initiated remotely. There is no available exploit. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in vercel next.js up to 15.5.15/16.2.4. This issue affects an unknown code block. The manipulation with an unknown input leads to a cross site scripting vulnerability. Using CWE to declare the problem leads to 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. Impacted is integrity. The summary by CVE is:

Next.js is a React framework for building full-stack web applications. From 13.0.0 to before 15.5.16 and 16.2.5, applications that use beforeInteractive scripts together with untrusted content can be vulnerable to cross-site scripting. In affected versions, serialized script content was not escaped safely before being embedded into the document, which could allow attacker-controlled input to break out of the intended script context and execute arbitrary JavaScript in a visitor's browser. This vulnerability is fixed in 15.5.16 and 16.2.5.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-44580 since 05/06/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1059.007 according to MITRE ATT&CK.

The vulnerability scanner Nessus provides a plugin with the ID 314906 (Next.js Framework 13.x < 15.5.16 / 16.x < 16.2.5 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 (314906) and CERT Bund (WID-SEC-2026-1401). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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