CVE-2024-11018
📋 TL;DR
This critical vulnerability in Webopac from Grand Vice info allows unauthenticated remote attackers to upload malicious files and execute arbitrary code on the server. Attackers can achieve complete system compromise by uploading webshells. All systems running vulnerable versions of Webopac are affected.
💻 Affected Systems
- Webopac from Grand Vice info
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete server takeover with attacker gaining full administrative control, data exfiltration, lateral movement to other systems, and persistent backdoor installation.
Likely Case
Attackers upload webshells to establish persistent access, steal sensitive data, and use the compromised server for further attacks.
If Mitigated
With proper file upload validation and web application firewalls, exploitation attempts are blocked and logged for investigation.
🎯 Exploit Status
The vulnerability requires no authentication and involves simple file upload manipulation
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check with Grand Vice info for specific patched versions
Vendor Advisory: https://www.twcert.org.tw/en/cp-139-8214-64fa2-2.html
Restart Required: Yes
Instructions:
1. Contact Grand Vice info for patch details. 2. Apply the security patch to all Webopac installations. 3. Restart the Webopac service. 4. Verify the fix is working.
🔧 Temporary Workarounds
Implement File Upload Restrictions
allConfigure web server to block uploads of executable file types
# For Apache: Add to .htaccess
<FilesMatch "\.(php|php3|php4|php5|phtml|pl|cgi|exe|dll|bat|cmd|sh|bash)$">
Order Deny,Allow
Deny from all
</FilesMatch>
# For Nginx: Add to server block
location ~* \.(php|php3|php4|php5|phtml|pl|cgi|exe|dll|bat|cmd|sh|bash)$ {
deny all;
}
Implement Web Application Firewall
allDeploy WAF rules to block malicious file upload attempts
# Example ModSecurity rule
SecRule FILES_TMPNAMES "@rx \.(php|php3|php4|php5|phtml|pl|cgi|exe|dll|bat|cmd|sh|bash)$" \
"id:1001,phase:2,deny,status:403,msg:'Blocked malicious file upload'"
🧯 If You Can't Patch
- Isolate the Webopac server from the internet and restrict access to trusted networks only
- Implement strict file upload validation at the application level to only allow specific safe file types
🔍 How to Verify
Check if Vulnerable:
Test if you can upload files with executable extensions (like .php, .jsp, .asp) through Webopac's upload functionalityCheck Version:
Check Webopac version through admin interface or contact Grand Vice info supportVerify Fix Applied:
Attempt to upload executable files after patching - they should be rejected with proper error messages📡 Detection & Monitoring
Log Indicators:
- Unusual file uploads with executable extensions
- Multiple failed upload attempts
- Requests to unexpected file paths in upload directories
Network Indicators:
- POST requests to upload endpoints with executable file content
- Subsequent requests to uploaded files with suspicious parameters
SIEM Query:
source="webopac" AND (uri="*upload*" OR uri="*.php" OR uri="*.jsp" OR uri="*.asp") AND status=200