---
id: CVE-2026-108953
title: >-
  mac-shell-mcp before 2.0.0 contains an OS command injection vulnerability that
  allows MCP clients to bypass the command whitelist by injecting shell
  metacharacters into execute_command arguments
summary: >-
  mac-shell-mcp before 2.0.0 contains an OS command injection vulnerability that
  allows MCP clients to bypass the command whitelist by injecting shell
  metacharacters into execute_command arguments. Attackers or malicious prompts
  can call a…
severity: high
cvss: 7.8
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-78
published: '2026-10-12'
updated: '2026-10-12'
sourceUpdated: '2026-10-12T13:17:28.307'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-108953'
references:
  - url: 'https://github.com/cfdude/mac-shell-mcp'
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/cfdude/mac-shell-mcp/blob/1c1708201abb7a18c83075e1bf933e7a92cbeb9f/src/services/command-service.ts#L257-L340
    label: disclosure@vulncheck.com
  - url: >-
      https://github.com/cfdude/mac-shell-mcp/commit/932ce733cde07bb30b1f186303e6692dbb5d087a
    label: disclosure@vulncheck.com
  - url: 'https://github.com/cfdude/mac-shell-mcp/issues/45'
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/mac-shell-mcp-before-2.0.0-os-command-injection-via-execute-command-arguments
    label: disclosure@vulncheck.com
tags:
  - nvd
ingestedAt: '2026-10-12T14:50:34.109Z'
---

## Overview

mac-shell-mcp before 2.0.0 contains an OS command injection vulnerability that allows MCP clients to bypass the command whitelist by injecting shell metacharacters into execute_command arguments. Attackers or malicious prompts can call a safe command such as pwd with arguments like ';' to run forbidden commands as the server user without approval.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.