CVE-2023-44021
📋 TL;DR
This vulnerability in Tenda AC10U routers allows remote attackers to execute arbitrary code via a stack overflow in the formSetClientState function. Attackers can exploit this to gain full control of affected devices. Users running vulnerable firmware versions are affected.
💻 Affected Systems
- Tenda AC10U
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise leading to persistent backdoor installation, network traffic interception, and lateral movement to other devices on the network.
Likely Case
Remote code execution allowing attackers to modify router settings, intercept traffic, or use the device as part of a botnet.
If Mitigated
Limited impact if device is behind firewall with restricted WAN access and proper network segmentation.
🎯 Exploit Status
Public proof-of-concept available in GitHub repository. Stack overflow vulnerabilities in embedded devices are commonly weaponized.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Not available
Restart Required: Yes
Instructions:
1. Check Tenda website for firmware updates. 2. Download latest firmware for AC10U. 3. Log into router admin interface. 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 administration interface
Network segmentation
allIsolate router management interface to separate VLAN
🧯 If You Can't Patch
- Replace vulnerable device with supported model
- Place device behind firewall with strict inbound rules
🔍 How to Verify
Check if Vulnerable:
Check router firmware version in admin interface under System Status or System ToolsCheck Version:
Login to router web interface and check System Status pageVerify Fix Applied:
Verify firmware version has been updated to a version later than V15.03.06.49📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to formSetClientState endpoint
- Multiple failed exploitation attempts
- Unexpected router reboots
Network Indicators:
- Unusual outbound connections from router
- Traffic patterns suggesting device compromise
SIEM Query:
source="router_logs" AND (uri="*/goform/setClientState" OR message="*formSetClientState*")