CVE-2024-0538
📋 TL;DR
A critical stack-based buffer overflow vulnerability in Tenda W9 routers allows remote attackers to execute arbitrary code by manipulating the ssidIndex parameter in the formQosManage_auto function of the httpd component. This affects Tenda W9 routers running firmware version 1.0.0.7(4456). Attackers can exploit this without authentication to potentially take full control of affected devices.
💻 Affected Systems
- Tenda W9
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete device compromise, creation of persistent backdoors, network traffic interception, and lateral movement to other devices on the network.
Likely Case
Remote code execution allowing attackers to install malware, modify router settings, intercept network traffic, or use the device as part of a botnet.
If Mitigated
Limited impact if devices are behind firewalls with strict ingress filtering, though internal network compromise remains possible if exploited.
🎯 Exploit Status
Exploit details are publicly available in GitHub repositories. The vulnerability requires no authentication and has a straightforward exploitation path.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: None available
Restart Required: Yes
Instructions:
1. Check Tenda's official website for firmware updates. 2. If an update is available, download the latest firmware. 3. Access router admin interface. 4. Navigate to System Tools > Firmware Upgrade. 5. Upload and install the new firmware. 6. Reboot the router.
🔧 Temporary Workarounds
Disable remote management
allPrevent external access to the router's web management interface
Network segmentation
allIsolate affected routers from critical network segments
🧯 If You Can't Patch
- Replace affected Tenda W9 routers with devices from vendors that provide security updates
- Implement strict network access controls to limit traffic to affected routers
🔍 How to Verify
Check if Vulnerable:
Check router firmware version via admin interface: System Status > Firmware Version. If version is 1.0.0.7(4456), the device is vulnerable.Check Version:
No CLI command available. Must check through web interface at http://router_ip/Verify Fix Applied:
Verify firmware version has been updated to a version later than 1.0.0.7(4456) through the admin interface.📡 Detection & Monitoring
Log Indicators:
- Unusual HTTP POST requests to formQosManage_auto endpoint
- Large or malformed ssidIndex parameter values in HTTP requests
- Router crash or restart logs
Network Indicators:
- HTTP traffic to router management interface with abnormal parameter lengths
- Exploit pattern matching from public PoCs
SIEM Query:
http.method:POST AND http.uri:"/goform/formQosManage_auto" AND (http.param.ssidIndex.length > 100 OR http.param.ssidIndex contains non-numeric characters)