MotionEye v0.43.1b4 and before is vulnerable to OS Command Injection in configuration parameters such as image_file_name. Unsanitized user input is written to Motion configuration files, allowing remote authenticated attackers with admin access to achieve code execution when Motion is restarted.

Affected: PyPI: motioneye

## Summary A command injection vulnerability in MotionEye allows attackers to achieve Remote Code Execution (RCE) by supplying malicious values in configuration fields exposed via the Web UI. Because MotionEye writes user-supplied values directly into Motion configuration files without sanitization, attackers can inject shell syntax that is executed when the Motion process restarts. This issue enables full takeover of the MotionEye container and potentially the host environment (depending on container privileges).

## Details ### Root Cause: MotionEye accepts arbitrary strings from fields such as **image_file_name** and **movie_filename** in the Web UI. These are written directly into **/etc/motioneye/camera-*.conf**. When MotionEye restarts the Motion service (motionctl.start), the Motion binary reads this configuration. Because Motion treats these fields as shell-expandable, injected characters (e.g. $(), backticks) are interpreted as shell commands.

### Vulnerability flow: Dashboard (Web UI) ↓ ConfigHandler.set_config() ↓ camera-*.conf written ↓ motionctl.restart() ↓ Motion parses config → executes payload

### Affected code: The issue arises in how config.py handles user input before writing to config files. No sanitization or allowlisting is applied to filename fields.

### Proof of Concept (PoC)

The following steps reproduce the Remote Code Execution (RCE) vulnerability in MotionEye. Tested using the official Docker image.

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#### Environment Setu…