CVE-2025-64157
📋 TL;DR
This CVE describes a format string vulnerability in Fortinet FortiOS that allows authenticated administrators to execute arbitrary code or commands via specially crafted configuration inputs. The vulnerability affects multiple FortiOS versions from 7.0 through 7.6.4. Attackers with admin credentials can exploit this to gain unauthorized system access.
💻 Affected Systems
- Fortinet FortiOS
📦 What is this software?
Fortios by Fortinet
Fortios by Fortinet
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise allowing attackers to execute arbitrary code, pivot to other systems, steal sensitive data, or deploy ransomware across the network.
Likely Case
Privilege escalation leading to unauthorized administrative access, configuration changes, or lateral movement within the network.
If Mitigated
Limited impact due to proper access controls, network segmentation, and monitoring preventing successful exploitation.
🎯 Exploit Status
Exploitation requires admin credentials and knowledge of format string vulnerabilities. No public exploits available at this time.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: FortiOS 7.6.5, FortiOS 7.4.10, FortiOS 7.2.12, FortiOS 7.0.15
Vendor Advisory: https://fortiguard.fortinet.com/psirt/FG-IR-25-795
Restart Required: Yes
Instructions:
1. Backup current configuration. 2. Download appropriate firmware from Fortinet support portal. 3. Upload firmware to FortiGate device. 4. Install firmware update. 5. Reboot device. 6. Verify successful update.
🔧 Temporary Workarounds
Restrict Admin Access
allLimit administrative access to trusted IP addresses and implement multi-factor authentication
config system admin
edit admin_user
set trusthost1 192.168.1.0 255.255.255.0
set two-factor enable
end
Audit Admin Accounts
allReview and remove unnecessary admin accounts, enforce strong password policies
config system admin
show
config system admin
edit admin_user
set password ENC <encrypted_password>
end
🧯 If You Can't Patch
- Implement strict network segmentation to isolate FortiGate devices from critical systems
- Enable comprehensive logging and monitoring for suspicious admin activities and configuration changes
🔍 How to Verify
Check if Vulnerable:
Check FortiOS version via CLI: get system status | grep VersionCheck Version:
get system status | grep VersionVerify Fix Applied:
Verify version is updated to patched version: get system status | grep Version📡 Detection & Monitoring
Log Indicators:
- Unusual admin login patterns
- Configuration changes involving format strings
- Failed authentication attempts on admin accounts
Network Indicators:
- Unusual outbound connections from FortiGate devices
- Traffic patterns indicating command execution
SIEM Query:
source="fortigate" AND (event_type="admin_login" OR event_type="config_change") AND (user="admin" OR command="*format*")