fast-filesystem-mcp is vulnerable to command injection through handleGetDiskUsage function
Date: 2026-04
Affected: npm/fast-filesystem-mcp
Attack vector: command-injection
Category: vulnerability-disclosure
Severity: High
CVE: CVE-2025-67364
CVE-2026-5327
CWE: CWE-24
CWE-74
CVSS: 6.3 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L)

A security flaw has been discovered in efforthye fast-filesystem-mcp up to 3.5.1. The affected element is the function handleGetDiskUsage of the file src/index.ts. Performing a manipulation results in command injection. The attack is possible to be carried out remotely. The exploit has been released to the public and may be used for attacks. The project was informed of the problem early through an issue report but has not responded yet.


Mitigations:

Architectural layers (MAESTRO):