CVE-2019-19502
📋 TL;DR
This vulnerability allows remote authenticated users to inject and execute arbitrary PHP code through the pluginconfig.php file in Image Uploader and Browser for CKEditor. It affects all versions before 4.1.9 of this CKEditor plugin. Attackers with authenticated access can achieve remote code execution on the server.
💻 Affected Systems
- Image Uploader and Browser for CKEditor
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Full server compromise allowing attackers to execute arbitrary commands, access sensitive data, install malware, or pivot to other systems.
Likely Case
Remote code execution leading to data theft, website defacement, or installation of backdoors for persistent access.
If Mitigated
Limited impact if proper authentication controls, input validation, and file upload restrictions are in place.
🎯 Exploit Status
Exploitation requires authenticated access but is straightforward once authentication is obtained. Public proof-of-concept exists in the GitHub commit history.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 4.1.9 and later
Vendor Advisory: https://github.com/xsmo/Image-Uploader-and-Browser-for-CKEditor/commit/c293d38c8b99444e775d94c1af50c9676c6544d2
Restart Required: No
Instructions:
1. Download version 4.1.9 or later from the GitHub repository. 2. Replace the existing plugin files with the updated version. 3. Verify the pluginconfig.php file has proper input validation and sanitization.
🔧 Temporary Workarounds
Disable vulnerable plugin
allTemporarily disable the Image Uploader and Browser plugin in CKEditor configuration
Edit CKEditor config.js and remove or comment out the plugin configuration
Restrict file upload permissions
allLimit which authenticated users can access file upload functionality
Implement role-based access control for CKEditor plugin features
🧯 If You Can't Patch
- Implement strict input validation and sanitization for all user inputs to pluginconfig.php
- Apply web application firewall rules to block suspicious PHP code patterns in requests
🔍 How to Verify
Check if Vulnerable:
Check if plugin version is below 4.1.9 by examining the plugin files or checking the version in the plugin's source code.Check Version:
grep -r 'version' /path/to/ckeditor/plugins/imageuploader/ || cat /path/to/ckeditor/plugins/imageuploader/plugin.js | grep versionVerify Fix Applied:
Verify the pluginconfig.php file contains proper input validation and the version is 4.1.9 or higher.📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to pluginconfig.php
- PHP code execution attempts in web server logs
- Suspicious file upload patterns
Network Indicators:
- HTTP requests containing PHP code snippets in parameters
- Unusual outbound connections from web server
SIEM Query:
source="web_logs" AND (uri="*pluginconfig.php*" AND (method="POST" OR params CONTAINS "php" OR params CONTAINS "eval"))🔗 References
- https://github.com/xsmo/Image-Uploader-and-Browser-for-CKEditor/commit/c293d38c8b99444e775d94c1af50c9676c6544d2
- https://github.com/xsmo/Image-Uploader-and-Browser-for-CKEditor/compare/4.1.8...v4.1.9
- https://github.com/xsmo/Image-Uploader-and-Browser-for-CKEditor/pull/11
- https://github.com/xsmo/Image-Uploader-and-Browser-for-CKEditor/pull/11/commits/5c7a6b0e10504f08e2f50655541b767e276ce749
- https://visat.me/security/cve-2019-19502/
- https://github.com/xsmo/Image-Uploader-and-Browser-for-CKEditor/commit/c293d38c8b99444e775d94c1af50c9676c6544d2
- https://github.com/xsmo/Image-Uploader-and-Browser-for-CKEditor/compare/4.1.8...v4.1.9
- https://github.com/xsmo/Image-Uploader-and-Browser-for-CKEditor/pull/11
- https://github.com/xsmo/Image-Uploader-and-Browser-for-CKEditor/pull/11/commits/5c7a6b0e10504f08e2f50655541b767e276ce749
- https://visat.me/security/cve-2019-19502/
