CVE-2020-24549
📋 TL;DR
CVE-2020-24549 is an unrestricted file upload vulnerability in openMAINT that allows authenticated users to upload arbitrary JSP files to the web server. This enables remote code execution on the underlying server, affecting all openMAINT installations before version 1.1-2.4.2.
💻 Affected Systems
- openMAINT
📦 What is this software?
Openmaint by Openmaint
⚠️ Risk & Real-World Impact
Worst Case
Full compromise of the web server with attacker gaining complete control over the system, data theft, lateral movement to other systems, and persistent backdoor installation.
Likely Case
Authenticated attackers upload malicious JSP files to execute arbitrary commands, potentially compromising the server and accessing sensitive maintenance data.
If Mitigated
With proper network segmentation and least privilege access, impact limited to the openMAINT application server only.
🎯 Exploit Status
Exploit requires authenticated access; public exploit code available on Exploit-DB.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 1.1-2.4.2 and later
Vendor Advisory: https://www.openmaint.org/en/download/latest-version
Restart Required: Yes
Instructions:
1. Download openMAINT version 1.1-2.4.2 or later from official site. 2. Backup current installation and data. 3. Follow upgrade instructions in documentation. 4. Restart web application server.
🔧 Temporary Workarounds
File Upload Restriction
allConfigure web server to block JSP file uploads to openMAINT directories
# Configure web server (Apache/Nginx) to deny .jsp file uploads
# Example Apache: <Location /openmaint/uploads>\n <FilesMatch "\\.jsp$">\n Deny from all\n </FilesMatch>\n</Location>
Authentication Hardening
allImplement strong authentication controls and limit user privileges
# Review and restrict user permissions in openMAINT
# Implement MFA if available
# Regularly audit user accounts
🧯 If You Can't Patch
- Implement strict network segmentation to isolate openMAINT server from critical systems
- Deploy web application firewall (WAF) with rules to block JSP file uploads and suspicious requests
🔍 How to Verify
Check if Vulnerable:
Check openMAINT version in admin interface or by examining application files; versions before 1.1-2.4.2 are vulnerable.Check Version:
# Check version in openMAINT admin panel or examine release notes filesVerify Fix Applied:
Verify version is 1.1-2.4.2 or later and test that JSP file uploads are properly restricted.📡 Detection & Monitoring
Log Indicators:
- Unusual JSP file uploads in web server logs
- Multiple failed authentication attempts followed by successful login and file upload
- Execution of system commands via web requests
Network Indicators:
- HTTP POST requests with .jsp file extensions to openMAINT upload endpoints
- Unusual outbound connections from openMAINT server
SIEM Query:
source="web_server" AND (uri="*.jsp" OR method="POST" AND uri="/openmaint/*/upload*")