CVE-2024-42980
📋 TL;DR
This CVE describes a stack overflow vulnerability in Tenda FH1206 routers that allows attackers to cause Denial of Service (DoS) through specially crafted POST requests. The vulnerability affects users of Tenda FH1206 routers running firmware version v02.03.01.35, potentially disrupting network connectivity.
💻 Affected Systems
- Tenda FH1206
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete router crash requiring physical reboot, persistent network downtime, and potential remote code execution if the overflow can be leveraged for arbitrary code execution.
Likely Case
Router becomes unresponsive, requiring manual reboot to restore functionality, causing temporary network disruption for connected devices.
If Mitigated
If the router is behind a firewall blocking external POST requests to the vulnerable endpoint, impact is limited to internal network threats only.
🎯 Exploit Status
The GitHub reference contains technical details about the vulnerability, making exploitation straightforward for attackers with basic networking knowledge.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Not available
Restart Required: No
Instructions:
Check Tenda's official website for firmware updates. If an update is available, download it from the vendor's official support page and follow their firmware upgrade instructions.
🔧 Temporary Workarounds
Disable Remote Management
allPrevent external access to the router's web interface by disabling remote management features.
Firewall Block Vulnerable Endpoint
allConfigure network firewalls to block POST requests to the frmL7ImForm endpoint on the router's IP address.
🧯 If You Can't Patch
- Replace the vulnerable router with a different model that doesn't have this vulnerability
- Isolate the router on a separate network segment with strict access controls
🔍 How to Verify
Check if Vulnerable:
Check router firmware version via web interface at 192.168.0.1 or 192.168.1.1, login and navigate to System Status or About page.Check Version:
No CLI command available. Must check via web interface.Verify Fix Applied:
If a firmware update is released, verify the version number matches or exceeds the patched version specified by the vendor.📡 Detection & Monitoring
Log Indicators:
- Multiple POST requests to frmL7ImForm endpoint
- Router crash/reboot events in system logs
- Unusual traffic patterns to router management interface
Network Indicators:
- POST requests with large or malformed page parameters sent to router IP on port 80/443
- Sudden loss of connectivity to router management interface
SIEM Query:
source="router_logs" AND (uri="/goform/frmL7ImForm" OR message="crash" OR message="reboot")