CVE-2025-62676
📋 TL;DR
A local privilege escalation vulnerability in Fortinet FortiClient for Windows allows low-privileged attackers to write arbitrary files with elevated permissions via crafted named pipe messages. This affects FortiClientWindows versions 7.4.0-7.4.4, 7.2.0-7.2.12, and all 7.0 versions. Attackers must have local access to the system to exploit this vulnerability.
💻 Affected Systems
- Fortinet FortiClientWindows
📦 What is this software?
Forticlient by Fortinet
Forticlient by Fortinet
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise through arbitrary file writes leading to privilege escalation, persistence mechanisms, or disabling security controls.
Likely Case
Local privilege escalation allowing attackers to gain administrative privileges on compromised systems.
If Mitigated
Limited impact if proper access controls restrict local user accounts and named pipe permissions are hardened.
🎯 Exploit Status
Requires local access and ability to craft named pipe messages. No public exploit code available at this time.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 7.4.5 and later, 7.2.13 and later
Vendor Advisory: https://fortiguard.fortinet.com/psirt/FG-IR-25-661
Restart Required: Yes
Instructions:
1. Download latest FortiClient version from Fortinet support portal. 2. Uninstall current FortiClient. 3. Install updated version. 4. Restart system.
🔧 Temporary Workarounds
Restrict Named Pipe Access
windowsConfigure Windows security policies to restrict access to FortiClient named pipes
Use Windows Security Policy Editor to modify named pipe permissions
Remove Local User Access
windowsRestrict local user accounts on critical systems
net localgroup "Remote Desktop Users" /delete [username]
🧯 If You Can't Patch
- Implement strict least privilege access controls for local user accounts
- Monitor for suspicious named pipe creation and access attempts
🔍 How to Verify
Check if Vulnerable:
Check FortiClient version in About dialog or via 'wmic product get name,version' commandCheck Version:
wmic product where "name like 'FortiClient%'" get name,versionVerify Fix Applied:
Verify installed version is 7.4.5+ or 7.2.13+ and check for successful installation logs📡 Detection & Monitoring
Log Indicators:
- Unusual named pipe creation/access in Windows Event Logs
- FortiClient service errors or unexpected restarts
Network Indicators:
- Local named pipe communication anomalies
SIEM Query:
EventID=4688 AND ProcessName LIKE '%FortiClient%' AND CommandLine CONTAINS 'pipe'