CVE-2025-55852
📋 TL;DR
This buffer overflow vulnerability in Tenda AC8 routers allows attackers to execute arbitrary code by sending specially crafted requests to the formWifiBasicSet function. It affects users running Tenda AC8 v4 firmware version 16.03.34.06. Successful exploitation could lead to complete router compromise.
💻 Affected Systems
- Tenda AC8 v4
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to full router compromise, credential theft, network traffic interception, and pivot to internal network devices.
Likely Case
Router crash/reboot causing denial of service, or limited code execution allowing attacker to modify router settings.
If Mitigated
No impact if router is not internet-facing and network segmentation prevents access to management interface.
🎯 Exploit Status
Public GitHub repository contains detailed analysis and likely exploit code. Buffer overflow in web management interface.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Unknown
Restart Required: Yes
Instructions:
1. Check Tenda website for firmware updates. 2. Download latest firmware for AC8 v4. 3. Log into router admin panel. 4. Navigate to System Tools > Firmware Upgrade. 5. Upload and install new firmware. 6. Reboot router.
🔧 Temporary Workarounds
Disable remote management
allPrevent external access to router management interface
Change default admin credentials
allUse strong unique passwords for router admin account
🧯 If You Can't Patch
- Isolate router on separate VLAN with strict firewall rules
- Implement network monitoring for unusual traffic to router management interface
🔍 How to Verify
Check if Vulnerable:
Check router firmware version in admin panel under System Status or System Tools > Firmware UpgradeCheck Version:
Login to router web interface and check firmware version in System StatusVerify Fix Applied:
Verify firmware version is no longer 16.03.34.06 after update📡 Detection & Monitoring
Log Indicators:
- Multiple failed login attempts
- Unusual POST requests to formWifiBasicSet endpoint
- Router crash/reboot logs
Network Indicators:
- Unusual traffic to router management port (typically 80/443)
- Buffer overflow patterns in HTTP requests
SIEM Query:
source="router_logs" AND (uri="/goform/formWifiBasicSet" OR message="buffer overflow" OR message="segmentation fault")