CVE-2024-40400
📋 TL;DR
This vulnerability allows attackers to upload malicious files through Automad's image upload function, potentially leading to remote code execution. Any Automad v2.0.0 installation with the vulnerable image upload feature enabled is affected. Attackers can compromise the entire web server if successful.
💻 Affected Systems
- Automad
📦 What is this software?
Automad by Automad
Automad by Automad
Automad by Automad
Automad by Automad
Automad by Automad
⚠️ Risk & Real-World Impact
Worst Case
Complete server compromise allowing attackers to execute arbitrary commands, steal data, install backdoors, or pivot to internal networks.
Likely Case
Webshell deployment leading to data theft, defacement, or use as a foothold for further attacks.
If Mitigated
File upload blocked or sanitized, preventing malicious file execution while maintaining legitimate image upload functionality.
🎯 Exploit Status
Exploitation requires access to the image upload function, which may require authentication depending on configuration.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: v2.0.1 or later
Vendor Advisory: https://github.com/marcantondahmen/automad/issues/106
Restart Required: No
Instructions:
1. Backup your Automad installation and database. 2. Download the latest version from the official repository. 3. Replace all files except your data directory. 4. Clear any cached files. 5. Verify the upload functionality works with legitimate images.
🔧 Temporary Workarounds
Disable Image Upload
allTemporarily disable the vulnerable image upload functionality
Modify Automad configuration to remove or disable image upload endpoints
Web Server File Restriction
linuxConfigure web server to block execution of uploaded files
For Apache: Add 'php_flag engine off' to upload directory .htaccess
For Nginx: Add 'location ~* \.(php|phtml)$ { deny all; }' to upload directory
🧯 If You Can't Patch
- Implement strict file type validation (whitelist .jpg, .png, .gif only)
- Use web application firewall to block malicious file upload patterns
🔍 How to Verify
Check if Vulnerable:
Check if Automad version is exactly 2.0.0 and image upload is accessibleCheck Version:
Check Automad version in admin panel or read composer.json version fieldVerify Fix Applied:
Attempt to upload a file with PHP extension - should be rejected or not execute📡 Detection & Monitoring
Log Indicators:
- Unusual file uploads with non-image extensions
- Multiple failed upload attempts
- Uploads to unexpected directories
Network Indicators:
- POST requests to upload endpoints with suspicious file contents
- Unusual outbound connections after file uploads
SIEM Query:
source="web_server" AND (uri_path="*upload*" OR uri_path="*image*upload*") AND (file_extension="php" OR file_extension="phtml" OR file_extension="jsp")