CVE-2026-55580

Published: Ago 25, 2026 Last Modified: Ago 25, 2026

ExploitDB:

Other exploit source:

Google Dorks:

HIGH 8,6

Source: [email protected]

Attack Vector: local

Attack Complexity: low

Privileges Required: none

User Interaction: none

Confidentiality: N/A

Integrity: N/A

Availability: N/A

Description

AI Translation Available

mcp-shell is an MCP server for running shell commands securely, auditably, and on demand. Prior to 0.6.0, config.go initializes Security.Enabled to false, and when MCP_SHELL_SEC_CONFIG_FILE is unset, main.go starts the documented bare-binary deployment without a security policy. SecurityValidator.validateCommand in security.go then short-circuits and allows every command supplied to the shell_exec MCP tool, so an LLM connected over stdio can execute unrestricted OS commands as the mcp-shell process user. The README from-source installation and MCP client configuration omit MCP_SHELL_SEC_CONFIG_FILE, making the insecure state the documented default. This issue is fixed in version 0.6.0.

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

Stable

Abstraction: Base Structure: Simple

Common Consequences

Security Scopes Affected:

Confidentiality Integrity Availability Non-Repudiation

Potential Impacts:

Execute Unauthorized Code Or Commands Dos: Crash, Exit, Or Restart Read Files Or Directories Modify Files Or Directories Read Application Data Modify Application Data Hide Activities