CVE-2026-3727
📋 TL;DR
A stack-based buffer overflow vulnerability in Tenda F453 routers allows remote attackers to execute arbitrary code by manipulating the mit_linktype/PPPOEPassword parameters. This affects Tenda F453 router users running firmware version 1.0.0.3. Successful exploitation could lead to complete device compromise.
💻 Affected Systems
- Tenda F453
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to full router compromise, credential theft, network traffic interception, and lateral movement into connected networks.
Likely Case
Router takeover enabling DNS hijacking, network monitoring, or botnet recruitment.
If Mitigated
Denial of service or router crash requiring physical reset.
🎯 Exploit Status
Public exploit code exists and manipulation involves simple parameter overflow.
🛠️ 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. Navigate to System Tools > Firmware Upgrade. 5. Upload new firmware file. 6. Wait for reboot.
🔧 Temporary Workarounds
Disable WAN Management
allPrevent remote access to router management interface from internet
Network Segmentation
allIsolate router management interface to trusted network segment only
🧯 If You Can't Patch
- Replace affected router with different model/brand
- Implement strict firewall rules blocking all external access to router management ports
🔍 How to Verify
Check if Vulnerable:
Check router firmware version in admin interface under System Status > Firmware VersionCheck Version:
curl -s http://router-ip/goform/QuickIndex | grep versionVerify Fix Applied:
Verify firmware version is no longer 1.0.0.3 after update📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to /goform/QuickIndex with long parameter values
- Router reboot/crash logs
Network Indicators:
- HTTP requests with abnormally long mit_linktype or PPPOEPassword parameters
- Traffic to router management port from unexpected sources
SIEM Query:
http.url:"/goform/QuickIndex" AND (http.param:"mit_linktype=*" OR http.param:"PPPOEPassword=*") AND bytes > 1000