CVE-2018-7243
📋 TL;DR
An authorization bypass vulnerability in Schneider Electric's 66074 MGE Network Management Card allows remote attackers to gain full administrative access to affected MGE UPS and STS devices without authentication. This affects organizations using these specific Schneider Electric power management devices with the vulnerable network management card installed. Attackers can completely compromise device functionality and potentially impact connected systems.
💻 Affected Systems
- Schneider Electric 66074 MGE Network Management Card
- MGE UPS systems with affected card
- MGE STS systems with affected card
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of UPS/STS devices allowing attackers to shut down power to critical infrastructure, modify device configurations, or use devices as network pivots to attack connected systems.
Likely Case
Unauthorized access to device management interface leading to configuration changes, monitoring disruption, or device tampering that could cause power interruptions.
If Mitigated
Limited impact if devices are properly segmented and monitored, though unauthorized access to management interface still possible.
🎯 Exploit Status
Vulnerability allows bypassing authentication mechanism on web interface without requiring credentials or complex exploitation.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Firmware update provided by Schneider Electric
Vendor Advisory: https://www.schneider-electric.com/en/download/document/SEVD-2018-074-01/
Restart Required: Yes
Instructions:
1. Download firmware update from Schneider Electric portal. 2. Backup current configuration. 3. Apply firmware update via web interface or console. 4. Verify update applied successfully. 5. Restart device if required by update process.
🔧 Temporary Workarounds
Network Segmentation
allIsolate affected devices from untrusted networks and restrict access to management interface.
Access Control Lists
allImplement firewall rules to restrict access to port 80/443/TCP on affected devices to authorized management stations only.
🧯 If You Can't Patch
- Implement strict network segmentation to isolate affected devices from untrusted networks
- Disable web interface if not required and use alternative management methods
- Monitor network traffic to/from affected devices for unauthorized access attempts
🔍 How to Verify
Check if Vulnerable:
Check device firmware version via web interface or console and compare against patched version in vendor advisory.Check Version:
Check via web interface at http(s)://device-ip/ or console connection to device management interface.Verify Fix Applied:
Verify firmware version matches patched version and test authentication bypass is no longer possible.📡 Detection & Monitoring
Log Indicators:
- Unauthorized access attempts to web interface
- Configuration changes without proper authentication logs
- Multiple failed login attempts followed by successful access
Network Indicators:
- Unusual traffic patterns to device management ports
- Access from unauthorized IP addresses to port 80/443
- HTTP requests bypassing authentication endpoints
SIEM Query:
source_ip=* AND dest_port IN (80,443) AND dest_ip=[device_ip] AND (http_status=200 OR http_method=POST) AND NOT user_agent=[authorized_management_tool]