CVE-2020-9477
📋 TL;DR
CVE-2020-9477 is a critical authentication vulnerability in HUMAX HGA12R-02 routers where unauthenticated attackers can capture authentication packets and obtain cleartext passwords. This allows attackers to create new user accounts or take full control of affected devices. All users of HUMAX HGA12R-02 routers with firmware version 1.1.53 are affected.
💻 Affected Systems
- HUMAX HGA12R-02 router
📦 What is this software?
Hga12r 02 Firmware by Humaxdigital
⚠️ Risk & Real-World Impact
Worst Case
Complete device takeover, creation of persistent backdoor accounts, network compromise, and potential lateral movement to connected devices.
Likely Case
Unauthorized access to router administration, network configuration changes, and potential credential theft for other services.
If Mitigated
Limited to isolated network segments with strict access controls and monitoring.
🎯 Exploit Status
Exploitation requires packet capture during authentication attempts, which can be automated.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: https://uk.humaxdigital.com/network/hga12r-02/
Restart Required: No
Instructions:
No official patch available. Contact HUMAX support for firmware updates or consider device replacement.
🔧 Temporary Workarounds
Disable web management interface
allDisable the vulnerable web-based management interface if not required.
Access router CLI via SSH/Telnet and disable web interface (specific commands vary by device)
Restrict access with firewall rules
linuxLimit access to router management interface to trusted IP addresses only.
iptables -A INPUT -p tcp --dport 80 -s TRUSTED_IP -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -s TRUSTED_IP -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -j DROP
🧯 If You Can't Patch
- Replace affected devices with updated models or different vendors
- Isolate vulnerable routers in separate network segments with strict firewall rules
🔍 How to Verify
Check if Vulnerable:
Check router firmware version via web interface at http://router-ip/status or via SSH/Telnet using 'show version' command.Check Version:
curl http://router-ip/status | grep FirmwareVerify Fix Applied:
Verify firmware version is no longer 1.1.53. Test authentication while monitoring network traffic to ensure passwords are not transmitted in cleartext.📡 Detection & Monitoring
Log Indicators:
- Multiple failed authentication attempts followed by successful login from new IP
- Unusual user account creation events in router logs
Network Indicators:
- Packet capture activity targeting router management ports (80, 443, 8080)
- Cleartext password transmission in HTTP traffic
SIEM Query:
source="router_logs" AND (event_type="auth_failure" OR event_type="user_create") | stats count by src_ip