CVE-2026-75021
fastify-cli vulnerable to remote code execution via ignored explicit Inspector bind address
Description
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.
INFO
Published Date :
Sept. 8, 2026, 1:17 p.m.
Last Modified :
Sept. 8, 2026, 7:07 p.m.
Remotely Exploit :
No
Source :
ce714d77-add3-4f53-aff5-83d477b104bb
Affected Products
The following products are affected by CVE-2026-75021
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | HIGH | ce714d77-add3-4f53-aff5-83d477b104bb |
Solution
- Upgrade fastify-cli to version 8.0.1 or later.
- Configure the Inspector bind address correctly.
- Avoid using the debug flag with invalid bind addresses.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-75021.
| URL | Resource |
|---|---|
| https://cna.openjsf.org/security-advisories.html | |
| https://github.com/fastify/fastify-cli/security/advisories/GHSA-88v4-3ph7-r88m |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-75021 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-75021
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-75021 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-75021 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Sep. 08, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-75021', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-09-08T14:21:00.762047Z'} -
New CVE Received by ce714d77-add3-4f53-aff5-83d477b104bb
Sep. 08, 2026
Action Type Old Value New Value Added Description 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. Added CVSS V3.1 AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H Added CWE CWE-1327 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/75xxx/CVE-2026-75021.json">CVE-2026-75021</a> Added Reference https://cna.openjsf.org/security-advisories.html Added Reference https://github.com/fastify/fastify-cli/security/advisories/GHSA-88v4-3ph7-r88m