CVE-2022-41330
📋 TL;DR
This vulnerability allows unauthenticated attackers to execute cross-site scripting (XSS) attacks against Fortinet FortiOS and FortiProxy devices via crafted HTTP GET requests. Attackers can inject malicious scripts that execute in victims' browsers when they visit affected web interfaces. Affected users include organizations running vulnerable versions of FortiOS 6.2.0-6.2.11, 6.4.0-6.4.11, 7.0.0-7.0.9, 7.2.0-7.2.3 or FortiProxy before 7.0.7 and 7.2.0-7.2.1.
💻 Affected Systems
- Fortinet FortiOS
- Fortinet FortiProxy
📦 What is this software?
Fortios by Fortinet
Fortios by Fortinet
Fortios by Fortinet
Fortios by Fortinet
Fortiproxy by Fortinet
Fortiproxy by Fortinet
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of administrative sessions leading to credential theft, configuration changes, or installation of persistent backdoors on the firewall/proxy device.
Likely Case
Session hijacking, credential theft from administrators, or redirection to malicious sites when administrators access the web interface.
If Mitigated
Limited impact if proper network segmentation, web application firewalls, and input validation are in place to block malicious requests.
🎯 Exploit Status
XSS vulnerabilities are commonly weaponized. The unauthenticated nature and low complexity make this attractive to attackers.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: FortiOS: 6.2.12, 6.4.12, 7.0.10, 7.2.4; FortiProxy: 7.0.7, 7.2.2
Vendor Advisory: https://fortiguard.com/psirt/FG-IR-22-363
Restart Required: Yes
Instructions:
1. Download the appropriate firmware version from Fortinet support portal. 2. Backup current configuration. 3. Upload and install the firmware update via web interface or CLI. 4. Reboot the device after installation.
🔧 Temporary Workarounds
Disable Web Management Interface
allDisable HTTP/HTTPS administrative access to reduce attack surface
config system global
set admin-https-redirect disable
set admin-sport 0
end
Restrict Management Access
allLimit administrative access to trusted IP addresses only
config system interface
edit <interface_name>
set allowaccess ping https ssh
set trust-ip-1 <trusted_ip>
end
🧯 If You Can't Patch
- Implement a web application firewall (WAF) in front of the Fortinet device to filter malicious requests
- Disable the web management interface entirely and use CLI/API management only
🔍 How to Verify
Check if Vulnerable:
Check current firmware version via CLI: 'get system status' or web interface System > DashboardCheck Version:
get system status | grep VersionVerify Fix Applied:
Verify firmware version matches patched versions: FortiOS 6.2.12+, 6.4.12+, 7.0.10+, 7.2.4+ or FortiProxy 7.0.7+, 7.2.2+📡 Detection & Monitoring
Log Indicators:
- Unusual HTTP GET requests with script tags or encoded payloads in web interface logs
- Multiple failed login attempts followed by successful login from unusual locations
Network Indicators:
- HTTP requests containing JavaScript payloads to Fortinet management interfaces
- Unusual outbound connections from Fortinet devices after web interface access
SIEM Query:
source="fortinet" AND (url="*<script>*" OR url="*javascript:*" OR url="*onload=*" OR url="*onerror=*")