fastify-cli up to 8.0.0 Inspector code injection

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.5$0-$5k1.62+

Summaryinfo

A vulnerability classified as critical has been found in fastify-cli up to 8.0.0. Impacted is an unknown function of the component Inspector. This manipulation causes code injection. This vulnerability is handled as CVE-2026-75021. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability has been found in fastify-cli up to 8.0.0 and classified as critical. Affected by this vulnerability is some unknown processing of the component Inspector. The manipulation with an unknown input leads to a code injection vulnerability. The CWE definition for the vulnerability is CWE-94. The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

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.

It is possible to read the advisory at github.com. This vulnerability is known as CVE-2026-75021 since 08/17/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1059 according to MITRE ATT&CK.

Upgrading to version 8.0.1 eliminates this vulnerability.

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

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.7
VulDB Meta Temp Score: 7.5

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 8.1
CNA Vector (openjs): 🔒

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Code injection
CWE: CWE-94 / CWE-74 / CWE-707
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: fastify-cli 8.0.1

Timelineinfo

08/17/2026 CVE reserved
09/08/2026 +22 days Advisory disclosed
09/08/2026 +0 days VulDB entry created
09/08/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-75021 (🔒)
GCVE (CVE): GCVE-0-2026-75021
GCVE (VulDB): GCVE-100-399811

Entryinfo

Created: 09/08/2026 15:09
Changes: 09/08/2026 15:09 (63)
Complete: 🔍
Cache ID: 216::103

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

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