CVE-2026-75021

fastify-cli starts the Node.js Inspector when a debug flag is used, but it ignores the explicit bind address the user supplies and binds the Inspector to a broadly reachable address instead of the intended loopback. As a result the debugging interface can be exposed beyond the local machine, and because the Inspector protocol allows arbitrary code evaluation, a remote party that reaches it can achieve remote code execution on the developer's machine. This affects fastify-cli from 1.5.0 up to 8.0.1. Users should upgrade to fastify-cli 8.0.1, which honors the configured Inspector bind address.

  • Published Sep 8, 2026
  • CVSS 8.1 high
  • 0.7% chance of exploitation in the next 30 days (EPSS)

Affected software

CVE-2026-75021 at the National Vulnerability Database