CVE-2025-7614
📋 TL;DR
This critical vulnerability in TOTOLINK T6 routers allows remote attackers to execute arbitrary commands via command injection in the delDevice function. Attackers can exploit this by sending specially crafted HTTP POST requests to the vulnerable CGI endpoint. All users running affected firmware versions are at risk.
💻 Affected Systems
- TOTOLINK T6
📦 What is this software?
T6 Firmware by Totolink
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise allowing persistent backdoor installation, network traffic interception, and lateral movement to other devices on the network.
Likely Case
Remote code execution leading to device takeover, credential theft, and use as pivot point for further attacks.
If Mitigated
Limited impact if device is behind firewall with restricted inbound access and proper network segmentation.
🎯 Exploit Status
Public proof-of-concept exploit code is available, making exploitation trivial for attackers with basic skills.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: None available at this time
Restart Required: No
Instructions:
1. Monitor TOTOLINK official website for firmware updates
2. Download and install any available security patches
3. Verify the patch addresses CVE-2025-7614
🔧 Temporary Workarounds
Disable Web Management Interface
allDisable the vulnerable CGI interface if not required for operations
Network Access Control
linuxRestrict access to router management interface using firewall rules
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -j DROP
🧯 If You Can't Patch
- Isolate affected devices in separate VLAN with strict firewall rules
- Implement network monitoring for suspicious HTTP POST requests to /cgi-bin/cstecgi.cgi
🔍 How to Verify
Check if Vulnerable:
Check firmware version via web interface at System Status > Firmware VersionCheck Version:
curl -s http://router-ip/ | grep -i firmwareVerify Fix Applied:
Verify firmware version is newer than 4.1.5cu.748 and test with known exploit payloads📡 Detection & Monitoring
Log Indicators:
- HTTP POST requests to /cgi-bin/cstecgi.cgi with suspicious ipAddr parameters
- Command execution patterns in system logs
Network Indicators:
- Unusual outbound connections from router
- HTTP requests containing shell metacharacters in ipAddr parameter
SIEM Query:
source="router_logs" AND uri_path="/cgi-bin/cstecgi.cgi" AND method="POST" AND (param="ipAddr" AND value MATCHES "[;&|`$()]+")