CVE-2026-55582

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

ExploitDB:

Other exploit source:

Google Dorks:

HIGH 8,4

Source: [email protected]

Attack Vector: local

Attack Complexity: low

Privileges Required: none

User Interaction: none

Scope: unchanged

Confidentiality: high

Integrity: high

Availability: high

Description

AI Translation Available

mcp-shell is an MCP server for running shell commands securely, auditably, and on demand. Prior to 0.6.0, the default security.yaml allows /usr/bin/git, while security.go omits ! from containsShellMetacharacters and containsDangerousShellConstructs and applies no per-executable argument policy. A caller of the shell_exec MCP tool can provide the command argument /usr/bin/git -c alias.pwn=!<arbitrary-command>, causing Git to create a shell alias and execute arbitrary OS commands as the mcp-shell process user. The default Docker image runs as mcpuser with Git installed and secure mode enabled, so the bypass is exploitable in the default deployment without additional authentication beyond MCP connectivity. 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