CVE-2021-27426
📋 TL;DR
GE UR IED firmware versions prior to 8.1x with 'Basic' security variant have a factory mode that cannot be disabled, allowing unauthorized access. This affects industrial control systems using these devices, potentially enabling attackers to modify configurations or disrupt operations.
💻 Affected Systems
- GE UR IED (Intelligent Electronic Device)
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of industrial control system allowing unauthorized configuration changes, operational disruption, or safety system manipulation.
Likely Case
Unauthorized access to device configuration leading to operational changes or data exfiltration.
If Mitigated
Limited impact with proper network segmentation and access controls preventing exploitation.
🎯 Exploit Status
Exploitation requires network access to the device but leverages a built-in factory mode feature.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 8.1x or later
Vendor Advisory: https://www.gegridsolutions.com/Passport/Login.aspx
Restart Required: Yes
Instructions:
1. Download firmware version 8.1x or later from GE Grid Solutions portal. 2. Follow GE's firmware update procedures for UR IED devices. 3. Verify successful update and factory mode status.
🔧 Temporary Workarounds
Network Segmentation
allIsolate UR IED devices in dedicated industrial network segments with strict firewall rules.
Access Control Lists
allImplement strict network access controls to limit communication to authorized systems only.
🧯 If You Can't Patch
- Implement strict network segmentation and firewall rules to isolate affected devices
- Monitor network traffic for unauthorized access attempts to factory mode features
🔍 How to Verify
Check if Vulnerable:
Check firmware version in device configuration interface; if below 8.1x with Basic security variant, device is vulnerable.Check Version:
Check via device configuration interface or management software; no universal CLI command available.Verify Fix Applied:
Confirm firmware version is 8.1x or later and factory mode is properly disabled in configuration.📡 Detection & Monitoring
Log Indicators:
- Unauthorized access attempts to factory mode
- Configuration changes from unexpected sources
Network Indicators:
- Unexpected traffic to UR IED management ports
- Factory mode protocol usage
SIEM Query:
source_ip:industrial_network AND dest_port:management_port AND action:configuration_change