CVE-2024-7182
📋 TL;DR
A critical buffer overflow vulnerability in TOTOLINK A3600R routers allows remote attackers to execute arbitrary code by manipulating the FileName parameter in the firmware upgrade function. This affects users of TOTOLINK A3600R version 4.1.2cu.5182_B20201102 who have the vulnerable CGI endpoint exposed. Successful exploitation could lead to complete device compromise.
💻 Affected Systems
- TOTOLINK A3600R
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to full router compromise, credential theft, network pivoting, and persistent backdoor installation.
Likely Case
Router takeover enabling traffic interception, DNS manipulation, and lateral movement into connected networks.
If Mitigated
Limited impact if the vulnerable endpoint is not internet-facing and network segmentation prevents lateral movement.
🎯 Exploit Status
Public exploit details available on GitHub, making exploitation straightforward for attackers with basic skills.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: None available
Restart Required: No
Instructions:
No official patch available. Vendor was contacted but did not respond. Consider workarounds or replacement.
🔧 Temporary Workarounds
Block CGI Endpoint Access
linuxUse firewall rules to block access to the vulnerable /cgi-bin/cstecgi.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
Disable Web Management Interface
allTurn off the router's web management interface if not required
Check router admin interface for web management toggle
🧯 If You Can't Patch
- Isolate affected routers in separate VLAN with strict firewall rules
- Implement network monitoring for exploitation attempts against the CGI endpoint
🔍 How to Verify
Check if Vulnerable:
Check router firmware version via web interface at 192.168.1.1 or using command: curl -s http://router-ip/ | grep -i versionCheck Version:
curl -s http://192.168.1.1/ | grep -o 'Firmware Version:[^<]*' || echo 'Check web interface manually'Verify Fix Applied:
No official fix available. Verify workarounds by testing if /cgi-bin/cstecgi.cgi endpoint is inaccessible.📡 Detection & Monitoring
Log Indicators:
- Multiple POST requests to /cgi-bin/cstecgi.cgi with long FileName parameters
- Unusual process execution from web server context
Network Indicators:
- HTTP POST requests to /cgi-bin/cstecgi.cgi with oversized payloads
- Unusual outbound connections from router
SIEM Query:
source="router_logs" AND url="/cgi-bin/cstecgi.cgi" AND method="POST" AND content_length>1000🔗 References
- https://github.com/abcdefg-png/IoT-vulnerable/blob/main/TOTOLINK/A3600R/setUpgradeFW.md
- https://vuldb.com/?ctiid.272603
- https://vuldb.com/?id.272603
- https://vuldb.com/?submit.378051
- https://github.com/abcdefg-png/IoT-vulnerable/blob/main/TOTOLINK/A3600R/setUpgradeFW.md
- https://vuldb.com/?ctiid.272603
- https://vuldb.com/?id.272603
- https://vuldb.com/?submit.378051
