CVE-2018-20444
📋 TL;DR
This vulnerability in Technicolor CGA0111 devices allows remote attackers to retrieve Wi-Fi credentials via SNMP requests using specific OIDs. Affected are Technicolor CGA0111 and CGA0111E-ES-13-E23E-c8000r5712-170217-0829-TRU devices with default configurations.
💻 Affected Systems
- Technicolor CGA0111
- Technicolor CGA0111E-ES-13-E23E-c8000r5712-170217-0829-TRU
📦 What is this software?
Cga0111 Firmware by Technicolor
⚠️ Risk & Real-World Impact
Worst Case
Attackers gain unauthorized access to the Wi-Fi network, potentially compromising all connected devices and enabling further lateral movement.
Likely Case
Wi-Fi credentials are stolen, allowing unauthorized network access and potential eavesdropping on network traffic.
If Mitigated
With SNMP disabled or properly secured, the vulnerability cannot be exploited, maintaining network confidentiality.
🎯 Exploit Status
Exploitation requires only SNMP access to the device and knowledge of the specific OIDs. No authentication needed.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Not publicly available
Restart Required: No
Instructions:
No official patch available. Apply workarounds instead.
🔧 Temporary Workarounds
Disable SNMP
allDisable SNMP service on affected devices to prevent credential exposure.
Access device admin interface → Network → SNMP → Disable SNMP
Restrict SNMP Access
allConfigure SNMP to only allow access from trusted IP addresses.
Access device admin interface → Network → SNMP → Set allowed IPs to trusted management network
Change SNMP Community Strings
allChange default SNMP community strings to strong, unique values.
Access device admin interface → Network → SNMP → Change read/write community strings
🧯 If You Can't Patch
- Isolate affected devices in separate VLAN with strict network segmentation
- Implement network monitoring for SNMP requests to the vulnerable OIDs
🔍 How to Verify
Check if Vulnerable:
Use snmpwalk or similar tool to query OID 1.3.6.1.4.1.4413.2.2.2.1.5.4.1.14.1.3.10001 and 1.3.6.1.4.1.4413.2.2.2.1.18.1.2.3.4.1.2.10001. If they return Wi-Fi credentials, device is vulnerable.Check Version:
Check device web interface or use SNMP to query system information OIDsVerify Fix Applied:
After applying workarounds, repeat the SNMP query. It should return no data or access denied.📡 Detection & Monitoring
Log Indicators:
- SNMP access logs showing queries to the specific OIDs
- Failed authentication attempts after credential exposure
Network Indicators:
- SNMP traffic to port 161/UDP containing the vulnerable OIDs
- Unusual Wi-Fi connection attempts
SIEM Query:
source_port:161 AND (oid:"1.3.6.1.4.1.4413.2.2.2.1.5.4.1.14.1.3.10001" OR oid:"1.3.6.1.4.1.4413.2.2.2.1.18.1.2.3.4.1.2.10001")