CVE-2026-55581
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 Docker security.yaml includes /bin/bash in allowed_executables, while security.go validates only the first token and checkBlockedPatternsAndCommands does not reject the shell command-mode flag -c. A caller of the shell_exec MCP tool can provide the command argument `/bin/bash -c <arbitrary-command>`, which passes validation and reaches executor.go, where parseCommand and exec.CommandContext execute the arbitrary command as mcpuser outside the intended allowlist. This issue is fixed in version 0.6.0.
78
Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
StableCommon 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
Applicable Platforms
Technologies:
Not Technology-Specific, AI/ML, Web Server
183
Permissive List of Allowed Inputs
DraftCommon Consequences
Security Scopes Affected:
Access Control
Potential Impacts:
Bypass Protection Mechanism
Applicable Platforms
All platforms may be affected
1188
Initialization of a Resource with an Insecure Default
IncompleteCommon Consequences
Security Scopes Affected:
Other
Potential Impacts:
Varies By Context
Applicable Platforms
All platforms may be affected
https://github.com/sonirico/mcp-shell/commit/f31377fce6ec31114e5a4398c0e5270552…
https://github.com/sonirico/mcp-shell/pull/16
https://github.com/sonirico/mcp-shell/releases/tag/v0.6.0
https://github.com/sonirico/mcp-shell/security/advisories/GHSA-3x77-wg38-92r3