CVE-2023-29180
📋 TL;DR
A null pointer dereference vulnerability in Fortinet FortiOS and FortiProxy allows attackers to cause denial of service via specially crafted HTTP requests. This affects multiple versions of both products, potentially disrupting network services for organizations using vulnerable configurations.
💻 Affected Systems
- Fortinet FortiOS
- Fortinet FortiProxy
📦 What is this software?
Fortios by Fortinet
Fortios by Fortinet
Fortios by Fortinet
Fortios by Fortinet
Fortios by Fortinet
Fortiproxy by Fortinet
Fortiproxy by Fortinet
Fortiproxy by Fortinet
Fortiproxy by Fortinet
Fortiproxy by Fortinet
Fortiproxy by Fortinet
⚠️ Risk & Real-World Impact
Worst Case
Complete service disruption of affected Fortinet devices, requiring manual reboot and causing extended network downtime.
Likely Case
Temporary denial of service affecting specific services or interfaces on the device, potentially requiring restart of affected processes.
If Mitigated
Limited impact with proper network segmentation and rate limiting, potentially causing only brief service interruptions.
🎯 Exploit Status
Exploitation requires sending specially crafted HTTP requests to vulnerable interfaces. No authentication is required, making this easily exploitable.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: FortiOS: 7.2.5, 7.0.12, 6.4.13, 6.2.15, 6.0.17; FortiProxy: 7.2.4, 7.0.11, 2.0.13, 1.2.14, 1.1.7, 1.0.8
Vendor Advisory: https://fortiguard.com/psirt/FG-IR-23-111
Restart Required: Yes
Instructions:
1. Download appropriate firmware version from Fortinet support portal. 2. Backup current configuration. 3. Upload firmware via web interface or CLI. 4. Reboot device after installation. 5. Verify version and functionality.
🔧 Temporary Workarounds
Restrict HTTP Access
allLimit HTTP access to management interfaces using firewall rules and network segmentation.
config firewall policy
edit 0
set srcintf "wan1"
set dstintf "internal"
set srcaddr "trusted_networks"
set dstaddr "fortigate_ip"
set service "HTTP HTTPS"
set action accept
next
Enable Rate Limiting
allConfigure rate limiting on HTTP interfaces to reduce impact of potential DoS attacks.
config system interface
edit "wan1"
set rate-limit-mode kernel-based
set egress-shape-rate 10000
set ingress-shape-rate 10000
next
🧯 If You Can't Patch
- Implement strict network segmentation to isolate vulnerable devices from untrusted networks
- Deploy WAF or IPS with HTTP anomaly detection to block malicious requests
🔍 How to Verify
Check if Vulnerable:
Check current firmware version via CLI: 'get system status' or web interface: System > Dashboard > System InformationCheck Version:
get system status | grep VersionVerify Fix Applied:
Verify version is patched: 'get system status' should show version equal to or higher than patched versions listed above📡 Detection & Monitoring
Log Indicators:
- Multiple HTTP requests causing process crashes
- System log entries showing service restarts
- High CPU/memory usage followed by service failure
Network Indicators:
- Unusual HTTP request patterns to management interfaces
- Multiple malformed HTTP requests from single sources
- Sudden drop in legitimate HTTP traffic
SIEM Query:
source="fortigate" AND (event_type="system" OR event_type="traffic") AND (message="*crash*" OR message="*restart*" OR message="*denial*" OR status="deny")