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How the CVE Works
CVE-2025-29287 exploits an insecure file upload mechanism in MCMS v5.4.3’s ueditor component. Attackers bypass file type validation, uploading malicious scripts (e.g., .jsp, .php) to the server. The lack of proper sanitization allows execution of these files, leading to remote code execution (RCE). The vulnerability stems from insufficient checks in the upload handler, permitting unauthorized file extensions and directory traversal.
DailyCVE Form
Platform: MCMS
Version: 5.4.3
Vulnerability: Arbitrary File Upload
Severity: Critical
Date: 04/24/2025
What Undercode Say:
Exploitation:
- Craft malicious file (e.g., `shell.jsp` with RCE payload).
2. Bypass upload checks using double extensions (`shell.jsp.jpg`).
- Trigger execution by accessing the uploaded file via web root.
Protection:
1. Patch MCMS to v5.4.4 or later.
2. Restrict uploads to whitelisted extensions.
3. Store files outside web root.
Detection Commands:
grep -r "fileUpload" /var/www/mcms/ueditor/ find /var/www/mcms/uploads -name ".jsp"
Mitigation Code (PHP):
$allowed = ['jpg', 'png'];
$ext = strtolower(pathinfo($_FILES['file']['name'], PATHINFO_EXTENSION));
if (!in_array($ext, $allowed)) { die("Invalid file."); }
Exploit Payload (Python):
import requests
files = {'file': ('shell.jsp', open('shell.jsp', 'rb'))}
requests.post("http://target.com/ueditor/upload", files=files)
Analytics:
- Attack Vector: Network (HTTP)
- Privilege Required: None
- User Interaction: Not needed
- Impact: Full system compromise
Log Monitoring:
tail -f /var/log/apache2/access.log | grep "POST /ueditor/upload"
Hardening Steps:
1. Disable script execution in uploads:
<Directory "/var/www/mcms/uploads"> php_flag engine off </Directory>
2. Implement WAF rules to block suspicious uploads.
3. Audit file permissions:
chmod -R 750 /var/www/mcms/uploads
Sources:
Reported By: nvd.nist.gov
Extra Source Hub:
Undercode
