CVE-2026-1331
📋 TL;DR
MeetingHub software from HAMASTAR Technology contains an unauthenticated arbitrary file upload vulnerability that allows remote attackers to upload malicious files and execute arbitrary code on the server. This affects all organizations using vulnerable versions of MeetingHub. Attackers can gain complete control of affected systems without authentication.
💻 Affected Systems
- MeetingHub by HAMASTAR Technology
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise leading to data theft, ransomware deployment, lateral movement within the network, and persistent backdoor installation.
Likely Case
Web shell installation enabling data exfiltration, credential harvesting, and use as a pivot point for further attacks.
If Mitigated
Limited impact with proper network segmentation, file upload restrictions, and web application firewalls in place.
🎯 Exploit Status
Simple file upload exploitation with publicly available proof-of-concept code.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check vendor advisory for specific patched version
Vendor Advisory: https://www.twcert.org.tw/en/cp-139-10651-ff09c-2.html
Restart Required: Yes
Instructions:
1. Check vendor advisory for patched version. 2. Backup configuration and data. 3. Apply vendor-provided patch or upgrade to fixed version. 4. Restart MeetingHub service. 5. Verify fix implementation.
🔧 Temporary Workarounds
Web Application Firewall Rules
allImplement WAF rules to block malicious file uploads and suspicious POST requests to upload endpoints.
# WAF rule to block suspicious file uploads
# Example: Block requests with executable extensions in upload parameters
File Upload Restrictions
linuxConfigure server to restrict file uploads to specific directories with proper permissions and file type validation.
# Apache: Set appropriate permissions on upload directories
# Nginx: Configure upload restrictions in server block
🧯 If You Can't Patch
- Isolate MeetingHub instances behind strict network segmentation with limited inbound/outbound access
- Implement application-level file type validation and restrict upload functionality to authenticated users only
🔍 How to Verify
Check if Vulnerable:
Test if unauthenticated file upload is possible by attempting to upload a test file to MeetingHub upload endpoints.Check Version:
Check MeetingHub admin interface or configuration files for version informationVerify Fix Applied:
Attempt the same unauthenticated file upload test after patching - it should be blocked or require authentication.📡 Detection & Monitoring
Log Indicators:
- Unusual file upload activity
- POST requests to upload endpoints from unauthenticated users
- Execution of unexpected files in web directories
Network Indicators:
- Unusual outbound connections from MeetingHub server
- Traffic patterns consistent with web shell communication
SIEM Query:
source="meetinghub.logs" AND (http_method="POST" AND uri_path CONTAINS "upload" AND user="-")