CVE-2021-26114
📋 TL;DR
This is a critical SQL injection vulnerability in FortiWAN that allows unauthenticated attackers to execute arbitrary SQL commands via crafted HTTP requests. Attackers could potentially execute unauthorized code or commands on affected systems. All FortiWAN deployments before version 4.5.9 are vulnerable.
💻 Affected Systems
- FortiWAN
📦 What is this software?
Fortiwan by Fortinet
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise allowing remote code execution, data exfiltration, and persistent backdoor installation
Likely Case
Database compromise leading to data theft, privilege escalation, and potential lateral movement within the network
If Mitigated
Limited impact with proper network segmentation and WAF protection blocking malicious SQL injection attempts
🎯 Exploit Status
SQL injection vulnerabilities are typically easy to exploit with readily available tools. The unauthenticated nature makes this particularly dangerous.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 4.5.9 and later
Vendor Advisory: https://fortiguard.com/psirt/FG-IR-21-062
Restart Required: Yes
Instructions:
1. Download FortiWAN version 4.5.9 or later from Fortinet support portal. 2. Backup current configuration. 3. Apply the firmware update through the web interface or CLI. 4. Reboot the device. 5. Verify the update was successful.
🔧 Temporary Workarounds
Network Segmentation
allIsolate FortiWAN devices from untrusted networks and restrict HTTP access to trusted IP addresses only
Web Application Firewall
allDeploy a WAF in front of FortiWAN to block SQL injection attempts
🧯 If You Can't Patch
- Immediately isolate the FortiWAN device from internet-facing networks
- Implement strict network access controls allowing only trusted management IPs to access the HTTP interface
🔍 How to Verify
Check if Vulnerable:
Check FortiWAN version via web interface or CLI. If version is below 4.5.9, the system is vulnerable.Check Version:
show system status (CLI) or check System Information in web interfaceVerify Fix Applied:
After patching, verify the version shows 4.5.9 or higher and test that SQL injection attempts are properly blocked📡 Detection & Monitoring
Log Indicators:
- Unusual SQL error messages in logs
- Multiple failed login attempts followed by successful access
- HTTP requests containing SQL keywords like UNION, SELECT, INSERT
Network Indicators:
- HTTP requests with SQL injection payloads to FortiWAN management interface
- Unusual outbound connections from FortiWAN device
SIEM Query:
source="fortiwan" AND (http_uri="*UNION*" OR http_uri="*SELECT*" OR http_uri="*INSERT*" OR http_uri="*DELETE*")