CVE-2023-40039
📋 TL;DR
This vulnerability allows remote attackers within Wi-Fi range to derive the default WPA2-PSK password by analyzing beacon frames from affected ARRIS modem/router devices. Attackers can then join the network without authentication, potentially compromising all connected devices. Affected users are those using default configurations on ARRIS TG852G, TG862G, and TG1672G devices.
💻 Affected Systems
- ARRIS TG852G
- ARRIS TG862G
- ARRIS TG1672G
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete network compromise allowing attackers to intercept all traffic, deploy malware to connected devices, pivot to internal networks, and maintain persistent access.
Likely Case
Unauthorized network access leading to data interception, device compromise, and potential credential theft from connected systems.
If Mitigated
Limited to unsuccessful connection attempts if strong custom passwords are used and network segmentation is implemented.
🎯 Exploit Status
Exploitation requires only Wi-Fi monitoring tools and proximity to the target network. No authentication or special privileges needed.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Not available
Vendor Advisory: Not available
Restart Required: No
Instructions:
No official patch exists. Change default Wi-Fi password immediately.
🔧 Temporary Workarounds
Change Default Wi-Fi Password
allReplace the default WPA2-PSK password with a strong, unique password to prevent derivation from beacon frames.
Access router admin interface (typically 192.168.0.1 or 192.168.1.1)
Navigate to Wireless Settings
Change WPA2-PSK password to strong random password (minimum 12 characters, mixed case, numbers, symbols)
Disable WPS and Enable WPA3 if Available
allDisable Wi-Fi Protected Setup (WPS) and enable WPA3 encryption for stronger protection.
Access router admin interface
Navigate to Wireless Security Settings
Disable WPS
Select WPA3 encryption if available
🧯 If You Can't Patch
- Implement network segmentation to isolate IoT devices from critical systems
- Enable MAC address filtering to restrict network access to known devices only
🔍 How to Verify
Check if Vulnerable:
Check if using default Wi-Fi password by accessing router admin interface and reviewing wireless security settings. Default passwords are often printed on device labels.Check Version:
Access router admin interface and check Firmware/System Information page for current version.Verify Fix Applied:
Verify new password is set by attempting to connect with old password (should fail) and new password (should succeed).📡 Detection & Monitoring
Log Indicators:
- Failed authentication attempts from unknown MAC addresses
- Multiple connection attempts with incorrect passwords
- New devices connecting to network
Network Indicators:
- Unusual traffic patterns from new MAC addresses
- Wi-Fi beacon frame analysis showing default password patterns
- ARP spoofing or MITM activity
SIEM Query:
source="router_logs" AND (event_type="auth_failure" OR event_type="new_device") AND NOT mac_address IN (known_devices)🔗 References
- https://github.com/actuator/cve/blob/main/Arris/CVE-2023-40039
- https://i.ebayimg.com/images/g/-UcAAOSwDe1kyD-Z/s-l1600.png
- https://i.ebayimg.com/images/g/4P0AAOSwdhxkrZtt/s-l1600.jpg
- https://github.com/actuator/cve/blob/main/Arris/CVE-2023-40039
- https://i.ebayimg.com/images/g/-UcAAOSwDe1kyD-Z/s-l1600.png
- https://i.ebayimg.com/images/g/4P0AAOSwdhxkrZtt/s-l1600.jpg
