CVE-2023-47267
📋 TL;DR
This vulnerability in TheGreenBow VPN clients allows attackers to escalate privileges by manipulating memory mapped files. Attackers could gain SYSTEM-level access on affected Windows systems. All users of the specified vulnerable VPN client versions are affected.
💻 Affected Systems
- TheGreenBow Windows Enterprise Certified VPN Client
- TheGreenBow Windows Standard VPN Client
- TheGreenBow Windows Enterprise VPN Client
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with SYSTEM privileges, enabling installation of malware, data theft, and persistent backdoors.
Likely Case
Local privilege escalation allowing attackers to bypass security controls and execute arbitrary code with elevated permissions.
If Mitigated
Limited impact if proper endpoint protection and least privilege principles are enforced, though privilege escalation remains possible.
🎯 Exploit Status
Requires local access to the system. The vulnerability involves memory manipulation which requires some technical sophistication.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check vendor advisory for latest patched versions
Vendor Advisory: https://www.thegreenbow.com/en/support/security-alerts/#deeplink-16093
Restart Required: Yes
Instructions:
1. Visit the vendor advisory URL. 2. Download the latest patched version. 3. Uninstall the vulnerable version. 4. Install the patched version. 5. Restart the system.
🔧 Temporary Workarounds
Remove vulnerable VPN client
windowsUninstall the vulnerable VPN client if not essential
Control Panel > Programs > Uninstall a program > Select TheGreenBow VPN Client > Uninstall
Restrict local access
allImplement strict access controls to limit who can log into affected systems
🧯 If You Can't Patch
- Implement application whitelisting to prevent unauthorized execution
- Deploy endpoint detection and response (EDR) solutions with privilege escalation monitoring
🔍 How to Verify
Check if Vulnerable:
Check installed programs for TheGreenBow VPN Client version 6.52 or 6.87Check Version:
wmic product where name like "%TheGreenBow%" get versionVerify Fix Applied:
Verify the installed version is newer than 6.52/6.87 or the software is removed📡 Detection & Monitoring
Log Indicators:
- Unexpected privilege escalation events
- Suspicious process creation with SYSTEM privileges
- VPN client crash logs
Network Indicators:
- Unusual VPN connection patterns from compromised systems
SIEM Query:
EventID=4688 AND NewProcessName="*\system32\*" AND SubjectUserName!="SYSTEM" AND ParentProcessName="*TheGreenBow*"