CVE-2024-3879
📋 TL;DR
This critical vulnerability in Tenda W30E routers allows remote attackers to execute arbitrary code via a stack-based buffer overflow in the formSetCfm function. Attackers can exploit this without authentication to potentially take full control of affected devices. All users running vulnerable firmware versions are at risk.
💻 Affected Systems
- Tenda W30E
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise leading to persistent backdoor installation, network traffic interception, lateral movement to other devices, and botnet recruitment.
Likely Case
Remote code execution allowing attackers to modify router settings, intercept traffic, or use the device as a pivot point for further attacks.
If Mitigated
Limited impact if devices are behind firewalls with strict inbound filtering, though internal network compromise remains possible.
🎯 Exploit Status
Public exploit code exists in GitHub repositories, making exploitation straightforward for attackers.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: None available - vendor did not respond to disclosure
Restart Required: Yes
Instructions:
No official patch available. Check Tenda website for firmware updates. If unavailable, consider device replacement.
🔧 Temporary Workarounds
Network Segmentation
allIsolate affected routers in separate VLANs with strict firewall rules
Access Control
linuxBlock external access to router management interface (port 80/443)
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -j DROP
🧯 If You Can't Patch
- Replace affected devices with patched alternatives from different vendors
- Implement strict network monitoring and IDS/IPS rules to detect exploitation attempts
🔍 How to Verify
Check if Vulnerable:
Check router web interface for firmware version. If version is 1.0.1.25(633), device is vulnerable.Check Version:
Check router web interface at http://router-ip or use nmap scan for banner grabbingVerify Fix Applied:
Verify firmware version has been updated to a version later than 1.0.1.25(633)📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to /goform/setcfm with long funcpara1 parameters
- Router reboot events following suspicious requests
Network Indicators:
- HTTP requests to router IP with abnormal payload lengths
- Traffic patterns suggesting router compromise
SIEM Query:
source="router_logs" AND uri="/goform/setcfm" AND (param_length>100 OR contains(param,"funcpara1"))🔗 References
- https://github.com/abcdefg-png/IoT-vulnerable/blob/main/Tenda/W30E/formSetCfm.md
- https://vuldb.com/?ctiid.260913
- https://vuldb.com/?id.260913
- https://vuldb.com/?submit.312822
- https://github.com/abcdefg-png/IoT-vulnerable/blob/main/Tenda/W30E/formSetCfm.md
- https://vuldb.com/?ctiid.260913
- https://vuldb.com/?id.260913
- https://vuldb.com/?submit.312822
