CVE-2026-1601
📋 TL;DR
This vulnerability allows remote attackers to execute arbitrary commands on Totolink A7000R routers by exploiting a command injection flaw in the setUploadUserData function. Attackers can manipulate the FileName parameter to inject malicious commands, potentially gaining full control of affected devices. This affects users running vulnerable firmware versions on Totolink A7000R routers.
💻 Affected Systems
- Totolink A7000R
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ 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 for botnet activities.
Likely Case
Remote code execution leading to device takeover, credential theft, and potential lateral movement within the network.
If Mitigated
Limited impact if devices are behind firewalls with strict inbound filtering and network segmentation.
🎯 Exploit Status
Public proof-of-concept exploit available on GitHub. Attack can be launched remotely without authentication.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Not available
Restart Required: Yes
Instructions:
1. Check vendor website for firmware updates
2. Download latest firmware
3. Access router web interface
4. Navigate to firmware update section
5. Upload and apply new firmware
6. Reboot router
🔧 Temporary Workarounds
Network Isolation
allPlace affected routers behind firewalls with strict inbound filtering
Access Restriction
linuxRestrict web management interface access to trusted IP addresses 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 devices with supported models
- Implement network segmentation to isolate affected routers from critical systems
🔍 How to Verify
Check if Vulnerable:
Check firmware version in router web interface under System Status or About sectionsCheck Version:
curl -s http://router-ip/cgi-bin/cstecgi.cgi | grep -i 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 setUploadUserData
- Suspicious command execution patterns in system logs
- Unexpected file uploads or system modifications
Network Indicators:
- Unusual outbound connections from router to external IPs
- Traffic spikes from router to command-and-control servers
- Unexpected port scans originating from router
SIEM Query:
source="router_logs" AND uri="/cgi-bin/cstecgi.cgi" AND (method="POST" OR params="setUploadUserData")🔗 References
- https://github.com/xyh4ck/iot_poc/blob/main/TOTOLINK/A7000R/03_RCE_setUploadUserData_RCE.md
- https://github.com/xyh4ck/iot_poc/blob/main/TOTOLINK/A7000R/03_RCE_setUploadUserData_RCE.md#poc
- https://vuldb.com/?ctiid.343373
- https://vuldb.com/?id.343373
- https://vuldb.com/?submit.740760
- https://www.totolink.net/
- https://github.com/xyh4ck/iot_poc/blob/main/TOTOLINK/A7000R/03_RCE_setUploadUserData_RCE.md
