CVE-2022-27005
📋 TL;DR
This CVE describes a critical command injection vulnerability in Totolink routers that allows attackers to execute arbitrary commands via the hostName parameter in the setWanCfg function. Attackers can gain full control of affected routers, potentially compromising entire networks. Users of Totolink X5000R and A7000R routers with specific vulnerable firmware versions are affected.
💻 Affected Systems
- Totolink X5000R
- Totolink A7000R
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete router compromise leading to network takeover, credential theft, malware deployment, and persistent backdoor installation across connected devices.
Likely Case
Router takeover enabling DNS hijacking, traffic interception, credential harvesting, and lateral movement into connected networks.
If Mitigated
Limited impact with proper network segmentation, though router compromise still poses significant risk to directly connected devices.
🎯 Exploit Status
Exploit requires network access to router web interface; no authentication needed for vulnerable endpoint.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Not available
Restart Required: Yes
Instructions:
1. Check Totolink website for firmware updates
2. Download latest firmware for your model
3. Access router admin interface
4. Navigate to firmware upgrade section
5. Upload and apply new firmware
6. Reboot router
🔧 Temporary Workarounds
Network Segmentation
allIsolate routers from critical network segments
Access Control
linuxRestrict web interface access to trusted IPs only
iptables -A INPUT -p tcp --dport 80 -s TRUSTED_IP -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -s TRUSTED_IP -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -j DROP
🧯 If You Can't Patch
- Replace vulnerable routers with supported models
- Implement strict network monitoring and anomaly detection
🔍 How to Verify
Check if Vulnerable:
Check router firmware version via admin interface: System Status > Firmware VersionCheck Version:
curl -s http://router-ip/cgi-bin/cstecgi.cgi | grep firmwareVerify Fix Applied:
Verify firmware version matches non-vulnerable release after update📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to /cgi-bin/cstecgi.cgi with setWanCfg
- Suspicious commands in router logs
- Multiple failed login attempts followed by configuration changes
Network Indicators:
- Unusual outbound connections from router
- DNS queries to malicious domains
- Traffic redirection patterns
SIEM Query:
source="router.log" AND "setWanCfg" AND ("hostName=" OR "command=" OR "exec=")