CVE-2024-42737
📋 TL;DR
This vulnerability allows authenticated attackers to execute arbitrary operating system commands on TOTOLINK X5000r routers through command injection in the delBlacklist function. Attackers can gain full control of affected devices, potentially compromising network security. Only users running the specific vulnerable firmware version are affected.
💻 Affected Systems
- TOTOLINK X5000r
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device takeover leading to persistent backdoor installation, network traffic interception, lateral movement to other devices, and use as botnet node.
Likely Case
Local privilege escalation to root, installation of malware or backdoors, credential theft from connected devices, and network reconnaissance.
If Mitigated
Limited to authenticated users only, reducing attack surface but still allowing significant damage if credentials are compromised.
🎯 Exploit Status
Exploitation requires authentication but is straightforward once credentials are obtained. The GitHub reference contains technical details.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Unknown
Restart Required: No
Instructions:
Check TOTOLINK official website for firmware updates. If available, download and install the latest firmware through the router's web interface.
🔧 Temporary Workarounds
Disable remote administration
allPrevent external access to the router's web interface
Access router settings > Administration > Remote Management > Disable
Restrict admin access
allLimit admin interface access to specific IP addresses
Access router settings > Security > Access Control > Add allowed IPs
🧯 If You Can't Patch
- Isolate affected routers in separate network segments with strict firewall rules
- Implement network monitoring for unusual outbound connections or command execution patterns
🔍 How to Verify
Check if Vulnerable:
Check firmware version in router web interface: System > Firmware Upgrade. If version matches affected version, device is vulnerable.Check Version:
curl -s http://router-ip/cgi-bin/cstecgi.cgi -d '{"topicurl":"setting/getSysStatus"}' | grep versionVerify Fix Applied:
Verify firmware version has been updated to a version newer than v9.1.0cu.2350_b20230313📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to /cgi-bin/cstecgi.cgi with delBlacklist parameter containing shell metacharacters
- Multiple failed authentication attempts followed by successful login
Network Indicators:
- Unexpected outbound connections from router to external IPs
- Unusual traffic patterns from router to internal devices
SIEM Query:
source="router_logs" AND uri="/cgi-bin/cstecgi.cgi" AND (param="delBlacklist" OR data CONTAINS "delBlacklist") AND (data CONTAINS "|" OR data CONTAINS ";" OR data CONTAINS "`" OR data CONTAINS "$")