CVE-2023-33530
📋 TL;DR
This CVE describes a command injection vulnerability in Tenda G103 Gigabit GPON Terminal devices. Attackers with web management access can execute arbitrary commands to gain shell privileges on the device. Only users of Tenda G103 GPON terminals with specific firmware are affected.
💻 Affected Systems
- Tenda G103 Gigabit GPON Terminal
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Full device compromise allowing attacker to install persistent backdoors, intercept network traffic, pivot to internal networks, or use device as botnet node.
Likely Case
Attacker gains shell access to modify device configuration, disrupt services, or use device for further attacks on internal network.
If Mitigated
Limited impact if device is isolated, management interface is restricted, and proper authentication is enforced.
🎯 Exploit Status
Exploit requires authenticated access to web interface. Public proof-of-concept demonstrates command injection technique.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: http://tenda.com
Restart Required: Yes
Instructions:
1. Check Tenda website for firmware updates. 2. Download latest firmware for G103. 3. Access device web interface. 4. Navigate to firmware upgrade section. 5. Upload and apply new firmware. 6. Reboot device.
🔧 Temporary Workarounds
Restrict Web Management Access
allLimit access to device web interface to trusted IP addresses only
Configure firewall rules to restrict access to device management IP:443 to specific source IPs
Change Default Credentials
allEnsure strong, unique credentials are set for web management interface
Log into web interface and change admin password in system settings
🧯 If You Can't Patch
- Isolate device in separate VLAN with strict network segmentation
- Implement network monitoring for unusual outbound connections from device
🔍 How to Verify
Check if Vulnerable:
Check device firmware version via web interface: System Status > Firmware VersionCheck Version:
Check via web interface or SSH if available: cat /proc/version or show version commandsVerify Fix Applied:
Verify firmware version is no longer V1.0.0.5 after update📡 Detection & Monitoring
Log Indicators:
- Unusual command execution in device logs
- Multiple failed login attempts followed by successful login
- Configuration changes from unusual IP addresses
Network Indicators:
- Unexpected outbound connections from device
- Unusual traffic patterns to/from device management interface
SIEM Query:
source="tenda-g103" AND (event="command_execution" OR event="config_change")