GitHub Advisoryadvisory · npm

GHSA-39w2-rjm5-chcv Next.js has information disclosure in development server's Model Context Protocol endpoint

LOW Published 2026-10-07 Modified 2026-10-07 Official page ↗
Aliases
CVE-2026-94486
Ecosystem
npm
Packages
next
Severity
Low
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
Weaknesses
CWE-346
Reviewed
2026-10-07

Affected packages

• npm next: >= 16.0.0, < 16.3.8 → fixed in 16.3.8

Description

The Next.js development server (`next dev`) exposes a Model Context Protocol endpoint that does not verify which website a request originates from, allowing a malicious website visited by the developer to read sensitive development data — including the project's location on disk, source code snippets from error reports, the route inventory, and development logs. Only applications run with `next dev` are affected. Production deployments do not serve this endpoint.

Related

Alias · CVE (1)

  • CVE-2026-94486 Next.js is a React framework for building full-stack web applications. vulnerability

Weakness · CWE (1)

  • CWE-346 Origin Validation Error weakness

References