CVE-2023-30805
📋 TL;DR
Sangfor Next-Gen Application Firewall NGAF8.0.17 has an unauthenticated remote command injection vulnerability in the /LogInOut.php endpoint. Attackers can execute arbitrary operating system commands by sending crafted HTTP POST requests with shell meta-characters in the 'un' parameter. This affects all deployments running the vulnerable version.
💻 Affected Systems
- Sangfor Next-Gen Application Firewall (NGAF)
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise allowing attackers to install persistent backdoors, exfiltrate sensitive data, pivot to internal networks, and use the firewall as a launch point for further attacks.
Likely Case
Attackers gain shell access to the firewall appliance, potentially disabling security controls, intercepting traffic, or using the device for cryptocurrency mining or DDoS attacks.
If Mitigated
With proper network segmentation and access controls, impact is limited to the firewall appliance itself, though it could still be used to attack other systems if lateral movement is possible.
🎯 Exploit Status
Multiple security researchers have published proof-of-concept exploits. The vulnerability requires minimal technical skill to exploit with readily available tools.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: NGAF8.0.18 or later
Vendor Advisory: https://www.sangfor.com/security-advisory
Restart Required: Yes
Instructions:
1. Log into Sangfor NGAF management interface. 2. Navigate to System > Upgrade. 3. Download and install NGAF8.0.18 or later firmware. 4. Reboot the appliance after installation completes. 5. Verify the version has been updated.
🔧 Temporary Workarounds
Web Application Firewall Rule
allBlock or sanitize requests containing shell meta-characters in the 'un' parameter
Add WAF rule: Block POST requests to /LogInOut.php containing characters: ; & | ` $ ( ) { } [ ] < > ' "
Network Access Control
linuxRestrict access to the /LogInOut.php endpoint using firewall rules
iptables -A INPUT -p tcp --dport 443 -m string --string "/LogInOut.php" --algo bm -j DROP
🧯 If You Can't Patch
- Immediately isolate the NGAF appliance from the internet and restrict internal access to only necessary administrative IPs
- Implement network monitoring and IDS/IPS rules to detect and block exploitation attempts targeting this vulnerability
🔍 How to Verify
Check if Vulnerable:
Check the firmware version in the NGAF web interface under System > System Info. If version is NGAF8.0.17, the system is vulnerable.Check Version:
curl -k https://<ngaf-ip>/cgi-bin/login.cgi | grep versionVerify Fix Applied:
After patching, verify the version shows NGAF8.0.18 or later. Test by attempting to access /LogInOut.php with shell characters in the 'un' parameter - it should be blocked or sanitized.📡 Detection & Monitoring
Log Indicators:
- HTTP POST requests to /LogInOut.php containing shell meta-characters in parameters
- Unusual command execution patterns in system logs
- Failed login attempts with suspicious characters
Network Indicators:
- HTTP traffic to /LogInOut.php with unusual parameter values
- Outbound connections from the NGAF appliance to unexpected destinations
- Sudden spikes in traffic to the login endpoint
SIEM Query:
source="ngaf_logs" AND url="/LogInOut.php" AND (param="un" AND value MATCHES "[;&|`$(){}\[\]<>'\"]")🔗 References
- https://aws.amazon.com/marketplace/pp/prodview-uujwjffddxzp4
- https://labs.watchtowr.com/yet-more-unauth-remote-command-execution-vulns-in-firewalls-sangfor-edition/
- https://vulncheck.com/advisories/sangfor-ngaf-username-rce
- https://aws.amazon.com/marketplace/pp/prodview-uujwjffddxzp4
- https://labs.watchtowr.com/yet-more-unauth-remote-command-execution-vulns-in-firewalls-sangfor-edition/
- https://vulncheck.com/advisories/sangfor-ngaf-username-rce
