CVE-2020-22809
📋 TL;DR
This vulnerability in Windscribe VPN client allows local attackers to escalate privileges by exploiting an unquoted service path in the WindscribeService. Attackers can place malicious executables in paths that get executed with SYSTEM privileges. Only users running Windscribe v1.83 Build 20 on Windows systems are affected.
💻 Affected Systems
- Windscribe VPN Client
📦 What is this software?
Windscribe by Windscribe
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with SYSTEM privileges, allowing installation of persistent malware, credential theft, and full control over the affected system.
Likely Case
Local privilege escalation to SYSTEM, enabling attackers to bypass security controls, install additional malware, or access protected system resources.
If Mitigated
Limited impact if proper endpoint protection and least privilege principles are enforced, though local privilege escalation remains possible.
🎯 Exploit Status
Exploit requires local access to the system and ability to write to directories in the service path. Public exploit code is available on Exploit-DB.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Windscribe v2.0 and later
Vendor Advisory: https://windscribe.com/changelog
Restart Required: Yes
Instructions:
1. Download latest Windscribe version from official website. 2. Uninstall current version. 3. Install updated version. 4. Restart system to ensure service updates take effect.
🔧 Temporary Workarounds
Manually quote service path
windowsModify the WindscribeService registry entry to use quoted paths
sc config WindscribeService binPath= "\"C:\Program Files\Windscribe\WindscribeService.exe\""
Remove vulnerable service
windowsUninstall Windscribe or disable the vulnerable service
sc stop WindscribeService
sc delete WindscribeService
🧯 If You Can't Patch
- Restrict write permissions to directories in the Windscribe installation path
- Implement application whitelisting to prevent execution of unauthorized binaries in system directories
🔍 How to Verify
Check if Vulnerable:
Check if WindscribeService path is unquoted: sc qc WindscribeService | findstr BINARY_PATH_NAMECheck Version:
wmic product where name="Windscribe" get versionVerify Fix Applied:
Verify service path is quoted and Windscribe version is 2.0 or higher📡 Detection & Monitoring
Log Indicators:
- Windows Event ID 4688 showing execution from unusual paths
- Security logs showing privilege escalation attempts
Network Indicators:
- Unusual outbound connections from SYSTEM context following local user activity
SIEM Query:
source="windows" AND (event_id=4688 AND (process_path="*Windscribe*" AND parent_process="*services.exe*") OR (process_name="cmd.exe" OR "powershell.exe") AND parent_process="WindscribeService.exe")