CVE-2026-1547
📋 TL;DR
This CVE describes a remote command injection vulnerability in Totolink A7000R routers. Attackers can execute arbitrary commands on affected devices by manipulating the 'plugin_name' parameter in the setUnloadUserData function. This affects users running vulnerable firmware versions of the Totolink A7000R router.
💻 Affected Systems
- Totolink A7000R
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise allowing attackers to install malware, create persistent backdoors, pivot to internal networks, or use the device for botnet activities.
Likely Case
Attackers gain shell access to execute commands, potentially stealing credentials, modifying router settings, or launching attacks against other devices.
If Mitigated
Limited impact if device is behind firewall with restricted WAN access and proper network segmentation.
🎯 Exploit Status
Public proof-of-concept available on GitHub demonstrates remote exploitation.
🛠️ 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
3. Access router web interface
4. Navigate to firmware upgrade section
5. Upload and apply new firmware
6. Reboot router
🔧 Temporary Workarounds
Disable WAN Management
allPrevent external access to router management interface
Network Segmentation
allIsolate router on separate VLAN with restricted access
🧯 If You Can't Patch
- Disable remote management and restrict access to trusted IP addresses only
- Implement network monitoring and intrusion detection for suspicious traffic to router management interface
🔍 How to Verify
Check if Vulnerable:
Check firmware version in router web interface under System Status or About pageCheck Version:
curl -s http://router-ip/cgi-bin/cstecgi.cgi | grep versionVerify Fix Applied:
Verify firmware version has been updated to a version later than 4.1cu.4154📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to /cgi-bin/cstecgi.cgi with shell metacharacters in parameters
- Unexpected command execution in system logs
Network Indicators:
- HTTP requests containing shell commands in plugin_name parameter
- Outbound connections from router to suspicious IPs
SIEM Query:
source="router_logs" AND uri="/cgi-bin/cstecgi.cgi" AND (param="plugin_name" AND value MATCHES "[;&|`$()]+")🔗 References
- https://github.com/xyh4ck/iot_poc/blob/main/TOTOLINK/A7000R/01_RCE_setUnloadUserData_RCE.md
- https://github.com/xyh4ck/iot_poc/blob/main/TOTOLINK/A7000R/01_RCE_setUnloadUserData_RCE.md#poc
- https://vuldb.com/?ctiid.343231
- https://vuldb.com/?id.343231
- https://vuldb.com/?submit.739713
- https://www.totolink.net/
- https://github.com/xyh4ck/iot_poc/blob/main/TOTOLINK/A7000R/01_RCE_setUnloadUserData_RCE.md
- https://github.com/xyh4ck/iot_poc/blob/main/TOTOLINK/A7000R/01_RCE_setUnloadUserData_RCE.md#poc
