CVE-2024-5785
📋 TL;DR
This CVE describes a command injection vulnerability in Comtrend routers that allows authenticated users to execute arbitrary commands on the device by sending specially crafted POST requests to the '/boaform/admin/formUserTracert' endpoint. This affects Comtrend WLD71-T1_v2.0.201820 routers, specifically the GRG-4280us version. Attackers with valid credentials can gain command execution on the router.
💻 Affected Systems
- Comtrend router WLD71-T1
- Comtrend GRG-4280us
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Complete router compromise allowing attacker to reconfigure network settings, intercept traffic, pivot to internal networks, install persistent backdoors, or brick the device.
Likely Case
Authenticated attacker gains shell access to router, enabling network reconnaissance, traffic manipulation, and potential lateral movement to connected devices.
If Mitigated
Limited impact if strong authentication controls, network segmentation, and proper monitoring are in place to detect exploitation attempts.
🎯 Exploit Status
Exploitation requires authenticated access to the router's web interface. The vulnerability is in a specific form handler that doesn't properly sanitize user input before passing to system commands.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: https://www.incibe.es/en/incibe-cert/notices/aviso/multiple-vulnerabilities-comtrend-router
Restart Required: Yes
Instructions:
1. Check Comtrend vendor website for firmware updates. 2. Download appropriate firmware for your model. 3. Access router admin interface. 4. Navigate to firmware update section. 5. Upload and apply new firmware. 6. Reboot router after update completes.
🔧 Temporary Workarounds
Disable vulnerable endpoint via firewall
linuxBlock access to the vulnerable '/boaform/admin/formUserTracert' endpoint using router firewall rules
iptables -A INPUT -p tcp --dport 80 -m string --string "/boaform/admin/formUserTracert" --algo bm -j DROP
iptables -A INPUT -p tcp --dport 443 -m string --string "/boaform/admin/formUserTracert" --algo bm -j DROP
Restrict admin interface access
linuxLimit access to router admin interface to specific trusted IP addresses only
iptables -A INPUT -p tcp --dport 80 -s ! TRUSTED_IP -j DROP
iptables -A INPUT -p tcp --dport 443 -s ! TRUSTED_IP -j DROP
🧯 If You Can't Patch
- Replace affected routers with supported models from different vendors
- Implement network segmentation to isolate affected routers from critical systems
🔍 How to Verify
Check if Vulnerable:
Check router firmware version in admin interface. If version is WLD71-T1_v2.0.201820, the device is vulnerable.Check Version:
curl -s http://router-ip/ | grep -i firmware || ssh admin@router-ip 'cat /proc/version'Verify Fix Applied:
Verify firmware version has been updated to a newer version than WLD71-T1_v2.0.201820 in router admin interface.📡 Detection & Monitoring
Log Indicators:
- POST requests to '/boaform/admin/formUserTracert' with unusual parameters
- Multiple failed authentication attempts followed by successful login and POST to vulnerable endpoint
- Unusual command execution in router logs
Network Indicators:
- Unusual outbound connections from router to external IPs
- Traffic patterns suggesting router is being used as pivot point
- DNS queries for command and control domains from router
SIEM Query:
source="router_logs" AND (url="/boaform/admin/formUserTracert" OR cmd="tracert" OR cmd="ping") AND (user!="admin" OR param contains "|" OR param contains ";" OR param contains "&")