iOS Simulator MCP Server (ios-simulator-mcp) is a Model Context Protocol (MCP) server for interacting with iOS simulators. Versions prior to 1.3.3 are written in a way that is vulnerable to command injection vulnerability attacks as part of some of its MCP Server tool definition and implementation. The MCP Server exposes the tool "ui_tap" which relies on Node.js child process API "exec" which is an unsafe and vulnerable API if concatenated with untrusted user input. LLM exposed user input for "duration", "udid", and "x" and "y" args can be replaced with shell meta-characters like ";" or "&&" or others to change the behavior from running the expected command "idb" to another command. When LLMs are tricked through prompt injection (and other techniques and attack vectors) to call the tool with input that uses special shell characters such as "; rm -rf /tmp;#" and other payload variations, the full command-line text will be interepted by the shell and result in other commands except of "ps" executing on the host running the MCP Server. Version 1.3.3 contains a patch for the issue.