CVE-2021-27509
📋 TL;DR
This vulnerability in Visualware MyConnection Server allows unauthorized access to published reports due to improper access control. Attackers can view sensitive network performance data without proper authentication. Organizations using MyConnection Server versions before 11.0b build 5382 are affected.
💻 Affected Systems
- Visualware MyConnection Server
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete exposure of all published network performance reports containing sensitive organizational data, potentially revealing network topology, bandwidth usage patterns, and performance metrics to unauthorized parties.
Likely Case
Unauthorized users accessing published reports containing network performance data, potentially exposing internal network information and usage patterns.
If Mitigated
Limited exposure if reports contain minimal sensitive data or if additional access controls are implemented at network/application layers.
🎯 Exploit Status
Exploitation likely involves accessing report URLs directly or enumerating report IDs. No authentication bypass required for published reports.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 11.0b build 5382 or later
Vendor Advisory: https://myconnectionserver.visualware.com/support/newrelease.html
Restart Required: Yes
Instructions:
1. Download MyConnection Server 11.0b build 5382 or later from Visualware support site. 2. Backup current configuration. 3. Install the update following vendor instructions. 4. Restart the MyConnection Server service.
🔧 Temporary Workarounds
Disable Report Publishing
allTemporarily disable the report publishing feature to prevent unauthorized access.
Navigate to MyConnection Server admin interface > Reports > Settings > Disable 'Publish Reports'
Network Access Control
allRestrict access to MyConnection Server web interface using firewall rules.
# Example iptables rule for Linux
sudo iptables -A INPUT -p tcp --dport 80 -s trusted_network -j ACCEPT
# Windows Firewall
New-NetFirewallRule -DisplayName "Restrict MyConnection" -Direction Inbound -LocalPort 80 -RemoteAddress trusted_network -Action Allow
🧯 If You Can't Patch
- Implement web application firewall (WAF) rules to block unauthorized access to report URLs
- Enable authentication at reverse proxy/load balancer level for all MyConnection Server access
🔍 How to Verify
Check if Vulnerable:
Check MyConnection Server version in admin interface under Help > About. If version is earlier than 11.0b build 5382, system is vulnerable.Check Version:
Check admin interface or run: cat /path/to/myconnectionserver/version.txt (Linux) or check installed programs list (Windows)Verify Fix Applied:
After update, verify version shows 11.0b build 5382 or later. Test that published reports now require proper access codes.📡 Detection & Monitoring
Log Indicators:
- Unauthorized access attempts to report URLs
- Multiple failed authentication attempts on report access
Network Indicators:
- Unusual traffic patterns to report endpoints
- Access to report URLs from unexpected IP addresses
SIEM Query:
source="myconnectionserver.log" AND (url="*/report/*" OR url="*/published/*") AND NOT user="authenticated_user"