CVE-2024-42982
📋 TL;DR
This vulnerability in Tenda FH1206 routers allows attackers to cause a Denial of Service (DoS) by sending a specially crafted POST request that triggers a stack overflow. The vulnerability affects Tenda FH1206 routers running firmware version v02.03.01.35. Attackers can exploit this remotely without authentication to crash the device.
💻 Affected Systems
- Tenda FH1206
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device crash requiring physical reboot, potential for remote code execution if the overflow can be controlled precisely (though not confirmed in this CVE).
Likely Case
Router becomes unresponsive, requiring manual reboot to restore functionality, disrupting network connectivity for all connected devices.
If Mitigated
If the router is behind a firewall with strict inbound filtering, exploitation attempts are blocked, preventing DoS.
🎯 Exploit Status
The GitHub reference provides technical details that could be used to create an exploit. The vulnerability requires sending a crafted POST request to the vulnerable endpoint.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Not available
Restart Required: Yes
Instructions:
Check Tenda's official website or support portal for firmware updates. If an update is available, download and install it via the router's web interface, then reboot the device.
🔧 Temporary Workarounds
Block HTTP access to router
allPrevent external access to the router's web interface by configuring firewall rules to block inbound HTTP/HTTPS traffic to the router's IP.
Change default admin password
allWhile this doesn't fix the vulnerability, it reduces the risk of other attacks and is a good security practice.
🧯 If You Can't Patch
- Isolate the router on a separate network segment to limit blast radius if exploited.
- Monitor network traffic for unusual POST requests to the router's IP address.
🔍 How to Verify
Check if Vulnerable:
Check the router's firmware version via the web interface (typically under System Status or Advanced Settings). If it shows v02.03.01.35, it is vulnerable.Check Version:
Not applicable via command line; use router web interface at http://[router-ip] and navigate to firmware/version section.Verify Fix Applied:
After updating firmware, verify the version has changed from v02.03.01.35 to a newer version.📡 Detection & Monitoring
Log Indicators:
- Router logs showing crashes or reboots
- Web server logs with malformed POST requests to /goform/fromVirtualSer or similar endpoints
Network Indicators:
- Unusual HTTP POST requests to router IP on port 80/443 with large or malformed 'page' parameter
SIEM Query:
source="router_logs" AND (event="crash" OR event="reboot") OR http.method="POST" AND http.uri="/goform/fromVirtualSer" AND http.param.page="*"