CVE-2026-94486

Next.js is a React framework for building full-stack web applications. From 16.0.0 until 16.3.8, the next dev development server exposes a Model Context Protocol endpoint without reliably restricting cross-site requests. A malicious website visited by a developer can reach the endpoint and read the project's disk location, source code snippets from error reports, route inventory, and development logs. Production deployments do not serve this endpoint. This issue is fixed in version 16.3.8.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/vercel/next.js/commit/2d9f50a409312696145b82b3157aadb6b1fef476	Patch
https://github.com/vercel/next.js/releases/tag/v16.3.8	Release Notes
https://github.com/vercel/next.js/security/advisories/GHSA-39w2-rjm5-chcv	Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

05 Oct 2026, 14:58

Type	Values Removed	Values Added
References	~~() https://github.com/vercel/next.js/commit/2d9f50a409312696145b82b3157aadb6b1fef476 -~~	() https://github.com/vercel/next.js/commit/2d9f50a409312696145b82b3157aadb6b1fef476 - Patch
References	~~() https://github.com/vercel/next.js/releases/tag/v16.3.8 -~~	() https://github.com/vercel/next.js/releases/tag/v16.3.8 - Release Notes
References	~~() https://github.com/vercel/next.js/security/advisories/GHSA-39w2-rjm5-chcv -~~	() https://github.com/vercel/next.js/security/advisories/GHSA-39w2-rjm5-chcv - Vendor Advisory
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 5.4
First Time		Vercel Vercel next.js
CPE		cpe:2.3:a:vercel:next.js::::::node.js::*

02 Oct 2026, 16:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-02 16:16

Updated : 2026-10-05 14:58

NVD link : CVE-2026-94486

Mitre link : CVE-2026-94486

CVE.ORG link : CVE-2026-94486

JSON object : View

Products Affected

vercel

next.js

CWE

CWE-346

Origin Validation Error

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