CVE-2025-7154
📋 TL;DR
This critical vulnerability in TOTOLINK N200RE routers allows remote attackers to execute arbitrary operating system commands by manipulating the Hostname parameter in the cgi-bin/cstecgi.cgi endpoint. Attackers can exploit this command injection flaw to gain full control of affected devices. All users running vulnerable firmware versions are at risk.
💻 Affected Systems
- TOTOLINK N200RE
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise allowing attackers to install persistent backdoors, pivot to internal networks, intercept traffic, or use the device as part of a botnet.
Likely Case
Remote code execution leading to device takeover, credential theft, network reconnaissance, and potential lateral movement within the network.
If Mitigated
Limited impact if devices are behind firewalls with strict inbound filtering, though internal threats remain possible.
🎯 Exploit Status
Public exploit code is available on GitHub, making exploitation trivial for attackers with basic skills.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: https://www.totolink.net/
Restart Required: Yes
Instructions:
1. Check vendor website for firmware updates 2. Download latest firmware 3. Access router admin interface 4. Navigate to firmware upgrade section 5. Upload and apply new firmware 6. Reboot device
🔧 Temporary Workarounds
Network Segmentation and Access Control
allRestrict access to router management interface using firewall rules and network segmentation
Disable Remote Management
allTurn off remote administration features if not required
🧯 If You Can't Patch
- Isolate affected devices in a dedicated VLAN with strict firewall rules
- Implement network monitoring and intrusion detection for suspicious CGI requests
🔍 How to Verify
Check if Vulnerable:
Check firmware version in router web interface under System Status or Administration settingsCheck Version:
curl -s http://router-ip/cgi-bin/cstecgi.cgi (check response for version info) or check web interfaceVerify Fix Applied:
Verify firmware version has been updated to a version newer than the affected ones📡 Detection & Monitoring
Log Indicators:
- Unusual CGI requests to /cgi-bin/cstecgi.cgi with Hostname parameter containing shell metacharacters
- Multiple failed login attempts followed by CGI access
Network Indicators:
- HTTP POST requests to /cgi-bin/cstecgi.cgi with suspicious Hostname values
- Outbound connections from router to unknown IPs
SIEM Query:
source="router_logs" AND uri="/cgi-bin/cstecgi.cgi" AND (param="Hostname" AND value MATCHES "[;&|`$()]+")