Microsoft UFO's Mobile MCP press_key tool can inject ADB commands

The press_key tool in Microsoft UFO's Mobile MCP server has a command injection vulnerability that allows authenticated callers to execute arbitrary shell commands on an authorized Android device. The key_code parameter of press_key is a free-form string that is appended to adb shell input keyevent without validation, and the adb client joins the arguments after shell with spaces into a remote command without escaping, so shell metacharacters in key_code enter the Android remote shell command. Exploiting this vulnerability requires a valid UFO_MCP_API_KEY bearer token, an accessible Mobile MCP server, and adb installed on the host with an authorized device connected. The advisory states that this does not by itself constitute host OS command execution, Android root execution, or access to private app data beyond the Android shell user's permissions.