CVE-2023-37717
📋 TL;DR
This vulnerability allows remote attackers to execute arbitrary code on affected Tenda routers via a stack overflow in the fromDhcpListClient function. Attackers can exploit this by sending specially crafted requests to the vulnerable parameter, potentially gaining full control of the device. All users running the specified Tenda router models with vulnerable firmware versions are affected.
💻 Affected Systems
- Tenda F1202
- Tenda FH1202
- Tenda AC10
- Tenda AC1206
- Tenda AC7
- Tenda AC5
- Tenda AC9
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise leading to persistent backdoor installation, network traffic interception, lateral movement to other devices, and participation in botnets.
Likely Case
Remote code execution allowing attackers to modify router settings, intercept traffic, or use the device as a pivot point for further attacks.
If Mitigated
Limited impact if devices are behind firewalls with strict inbound filtering and network segmentation.
🎯 Exploit Status
Public proof-of-concept available in GitHub repository. Exploitation requires network access to the router's management interface.
🛠️ 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 your model. 3. Access router admin interface. 4. Navigate to firmware upgrade section. 5. Upload and apply new firmware. 6. Reboot router.
🔧 Temporary Workarounds
Network Segmentation
allIsolate affected routers from critical networks and internet exposure
Access Control
linuxRestrict access to router management interface using firewall rules
iptables -A INPUT -p tcp --dport 80 -s trusted_ip -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP
🧯 If You Can't Patch
- Replace affected devices with supported models from different vendors
- Implement strict network segmentation to isolate vulnerable routers
🔍 How to Verify
Check if Vulnerable:
Check router firmware version in admin interface and compare with affected versions listCheck Version:
curl -s http://router-ip/ | grep -i versionVerify Fix Applied:
Verify firmware version has been updated to a version not listed in affected versions📡 Detection & Monitoring
Log Indicators:
- Unusual HTTP POST requests to router management interface
- Multiple failed login attempts followed by successful access
- Unexpected firmware modification logs
Network Indicators:
- Unusual outbound connections from router
- Traffic patterns indicating command and control communication
- Port scanning originating from router
SIEM Query:
source="router_logs" AND (url="*fromDhcpListClient*" OR method="POST" AND uri="*cgi-bin*" AND size>1000)