CVE-2026-3398
📋 TL;DR
A buffer overflow vulnerability in Tenda F453 routers allows remote attackers to execute arbitrary code by sending specially crafted requests to the httpd component. This affects Tenda F453 router firmware version 1.0.0.3. Attackers can exploit this without authentication to potentially take full control of affected devices.
💻 Affected Systems
- Tenda F453
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete device compromise, lateral movement to internal networks, and persistent backdoor installation.
Likely Case
Router compromise allowing traffic interception, DNS hijacking, credential theft, and botnet recruitment.
If Mitigated
Limited impact if device is behind firewall with restricted WAN access and network segmentation.
🎯 Exploit Status
Public exploit code exists in GitHub repositories, making exploitation accessible to attackers with basic skills.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: https://www.tenda.com.cn/
Restart Required: Yes
Instructions:
1. Check Tenda website for firmware updates 2. Download latest firmware 3. Access router admin interface 4. Upload and apply firmware update 5. Reboot router
🔧 Temporary Workarounds
Disable WAN Management
allPrevent external access to router management interface
Access router admin > Advanced > Remote Management > Disable
Network Segmentation
allIsolate router management interface to separate VLAN
🧯 If You Can't Patch
- Replace affected routers with supported models
- Implement strict firewall rules blocking all external access to router management ports (typically 80, 443, 8080)
🔍 How to Verify
Check if Vulnerable:
Check router firmware version in admin interface. If version is 1.0.0.3, device is vulnerable.Check Version:
curl -s http://router-ip/ | grep -i version or check admin interface System StatusVerify Fix Applied:
Verify firmware version has been updated to a version later than 1.0.0.3.📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to /goform/AdvSetWan
- Multiple failed buffer overflow attempts
- Unexpected router reboots
Network Indicators:
- Malformed HTTP requests to router management interface
- Traffic patterns suggesting exploit attempts
SIEM Query:
source="router_logs" AND (uri="/goform/AdvSetWan" OR message="buffer overflow" OR message="segmentation fault")