CVE-2022-33877
📋 TL;DR
This vulnerability allows a local authenticated attacker to modify files in the FortiClient or FortiConverter installation folder when installed in an insecure location. It affects Windows installations of FortiClient versions 7.0.0-7.0.6 and 6.4.0-6.4.8, and FortiConverter versions 6.2.0-6.2.1, 7.0.0, and all 6.0.0 versions.
💻 Affected Systems
- FortiClient
- FortiConverter
📦 What is this software?
Forticlient by Fortinet
Forticlient by Fortinet
⚠️ Risk & Real-World Impact
Worst Case
Attacker gains SYSTEM privileges by replacing legitimate executables with malicious ones, leading to complete system compromise.
Likely Case
Attacker escalates privileges to modify configuration files or install malware within the application context.
If Mitigated
Limited impact if installed in secure folder with proper permissions, restricting file tampering.
🎯 Exploit Status
Requires local authenticated access and insecure installation folder. Simple file replacement attack.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: FortiClient 7.0.7+, 6.4.9+; FortiConverter 7.0.1+, 6.2.2+
Vendor Advisory: https://fortiguard.com/psirt/FG-IR-22-229
Restart Required: Yes
Instructions:
1. Download latest version from Fortinet support portal. 2. Uninstall vulnerable version. 3. Install patched version. 4. Restart system.
🔧 Temporary Workarounds
Secure Installation Folder
windowsReinstall application to secure folder (e.g., Program Files) with proper permissions.
Uninstall current version
Reinstall to C:\Program Files\Fortinet\
Restrict Folder Permissions
windowsModify installation folder permissions to remove write access for non-administrative users.
icacls "C:\Path\To\Installation" /deny Users:(OI)(CI)W
🧯 If You Can't Patch
- Monitor installation folder for unauthorized file modifications using file integrity monitoring.
- Restrict local user access to systems running vulnerable versions.
🔍 How to Verify
Check if Vulnerable:
Check installed version via Control Panel > Programs > Programs and Features, or run 'wmic product get name,version' in command prompt.Check Version:
wmic product where "name like 'Forti%'" get name,versionVerify Fix Applied:
Verify version is 7.0.7+ or 6.4.9+ for FortiClient, or 7.0.1+ or 6.2.2+ for FortiConverter.📡 Detection & Monitoring
Log Indicators:
- Windows Event Logs showing file modifications in Fortinet installation folders
- Unexpected process execution from Fortinet directories
Network Indicators:
- None - local attack only
SIEM Query:
EventID=4663 AND ObjectName LIKE '%Fortinet%' AND Accesses='WriteData'