CVE-2024-7180
📋 TL;DR
A critical buffer overflow vulnerability in TOTOLINK A3600R routers allows remote attackers to execute arbitrary code by manipulating the 'comment' parameter in the setPortForwardRules function. This affects devices running firmware version 4.1.2cu.5182_B20201102. Attackers can exploit this without authentication to potentially take full control of affected routers.
💻 Affected Systems
- TOTOLINK A3600R
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete device compromise, creation of persistent backdoors, lateral movement to internal networks, and botnet recruitment.
Likely Case
Remote code execution allowing attackers to modify router settings, intercept network traffic, or use the device as a pivot point for further attacks.
If Mitigated
Limited impact if device is behind strict network segmentation with no internet exposure, though internal exploitation risk remains.
🎯 Exploit Status
Public exploit code is available on GitHub. The vulnerability requires no authentication and has simple exploitation vectors.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: None available - vendor did not respond to disclosure
Restart Required: Yes
Instructions:
No official patch available. Consider replacing affected devices or implementing strict network controls.
🔧 Temporary Workarounds
Disable Port Forwarding Rules
allRemove all port forwarding rules to prevent access to the vulnerable endpoint
Access router web interface > Advanced > NAT Forwarding > Port Forwarding > Delete all rules
Block CGI Endpoint Access
linuxUse firewall rules to block access to the vulnerable CGI endpoint
iptables -A INPUT -p tcp --dport 80 -m string --string "/cgi-bin/cstecgi.cgi" --algo bm -j DROP
iptables -A INPUT -p tcp --dport 443 -m string --string "/cgi-bin/cstecgi.cgi" --algo bm -j DROP
🧯 If You Can't Patch
- Isolate affected routers in a dedicated VLAN with strict egress filtering
- Implement network-based intrusion prevention rules to detect and block exploitation attempts
🔍 How to Verify
Check if Vulnerable:
Check router firmware version via web interface (Login > System Tools > Firmware Upgrade) or via SSH: cat /proc/versionCheck Version:
curl -s http://router-ip/cgi-bin/cstecgi.cgi | grep -i version || ssh admin@router-ip 'cat /proc/version'Verify Fix Applied:
No official fix available. Verify workarounds by testing if /cgi-bin/cstecgi.cgi endpoint is inaccessible.📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to /cgi-bin/cstecgi.cgi with long comment parameters
- Multiple failed buffer overflow attempts in system logs
Network Indicators:
- HTTP requests with abnormally long comment parameter values
- Traffic patterns suggesting exploitation attempts
SIEM Query:
source="router_logs" AND (uri="/cgi-bin/cstecgi.cgi" AND (comment.length>100 OR method="POST" AND status=500))🔗 References
- https://github.com/abcdefg-png/IoT-vulnerable/blob/main/TOTOLINK/A3600R/setPortForwardRules.md
- https://vuldb.com/?ctiid.272601
- https://vuldb.com/?id.272601
- https://vuldb.com/?submit.378049
- https://github.com/abcdefg-png/IoT-vulnerable/blob/main/TOTOLINK/A3600R/setPortForwardRules.md
- https://vuldb.com/?ctiid.272601
- https://vuldb.com/?id.272601
- https://vuldb.com/?submit.378049
