CVE-2022-40681
📋 TL;DR
This vulnerability in Fortinet FortiClient for Windows allows attackers to cause denial of service by sending specially crafted requests to a specific named pipe. The flaw stems from incorrect authorization checks, enabling disruption of FortiClient functionality. Organizations using affected FortiClient versions on Windows systems are at risk.
💻 Affected Systems
- Fortinet FortiClient
📦 What is this software?
Forticlient by Fortinet
Forticlient by Fortinet
Forticlient by Fortinet
Forticlient by Fortinet
⚠️ Risk & Real-World Impact
Worst Case
Complete disruption of FortiClient functionality, potentially affecting VPN connectivity, endpoint protection, and security posture monitoring on affected systems.
Likely Case
Temporary denial of service affecting FortiClient services, requiring service restart or system reboot to restore functionality.
If Mitigated
Minimal impact with proper network segmentation and access controls limiting named pipe exposure to untrusted users.
🎯 Exploit Status
Exploitation requires ability to send crafted requests to the specific named pipe, which typically requires some level of system access. No public exploit code has been disclosed.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: FortiClient 7.0.8, 6.4.10, 6.2.10, 6.0.11 and later
Vendor Advisory: https://fortiguard.com/psirt/FG-IR-22-299
Restart Required: Yes
Instructions:
1. Download latest FortiClient version from Fortinet support portal. 2. Uninstall current FortiClient. 3. Install updated version. 4. Restart system to ensure all services are properly updated.
🔧 Temporary Workarounds
Restrict Named Pipe Access
windowsConfigure Windows security settings to restrict access to the vulnerable named pipe to only trusted users and processes.
Use Windows Security Policy or PowerShell to modify named pipe permissions: Get-Acl \\.\pipe\forticlient_pipe | Set-Acl -Path \\.\pipe\forticlient_pipe
Network Segmentation
allImplement network segmentation to limit which systems can communicate with FortiClient endpoints.
🧯 If You Can't Patch
- Implement strict access controls to limit which users and processes can interact with named pipes on affected systems.
- Monitor for unusual named pipe access attempts and implement additional endpoint security controls.
🔍 How to Verify
Check if Vulnerable:
Check FortiClient version in About section or via command: "FortiClient.exe --version" and compare against affected versions.Check Version:
FortiClient.exe --versionVerify Fix Applied:
Verify installed version is 7.0.8+, 6.4.10+, 6.2.10+, or 6.0.11+ and test FortiClient functionality remains stable during normal operations.📡 Detection & Monitoring
Log Indicators:
- Windows Event Logs showing access denied errors for named pipe operations
- FortiClient service crash or restart events
- Unusual named pipe connection attempts
Network Indicators:
- Multiple connection attempts to named pipes from unexpected sources
- Unusual inter-process communication patterns
SIEM Query:
EventID=4688 OR EventID=4663 AND ProcessName="FortiClient.exe" AND ObjectType="File" AND ObjectName LIKE "%pipe%forticlient%"