CVE-2020-7561
📋 TL;DR
CVE-2020-7561 is a critical authentication bypass vulnerability in Schneider Electric's Easergy T300 firmware that allows unauthenticated attackers to execute arbitrary commands, access sensitive information, or cause denial of service. This affects industrial control systems using Easergy T300 devices with firmware version 2.7 and older. Organizations using these devices in power distribution and industrial environments are at risk.
💻 Affected Systems
- Schneider Electric Easergy T300
📦 What is this software?
Easergy T300 Firmware by Schneider Electric
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of industrial control systems leading to equipment damage, power outages, or safety incidents through arbitrary command execution.
Likely Case
Unauthorized access to sensitive configuration data, manipulation of protection relay settings, or denial of service disrupting power monitoring.
If Mitigated
Limited impact if devices are behind firewalls with strict network segmentation and access controls.
🎯 Exploit Status
The vulnerability requires no authentication and has a simple exploitation path, making it attractive to attackers.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Firmware version 2.8 and newer
Vendor Advisory: https://www.se.com/ww/en/download/document/SEVD-2020-315-06/
Restart Required: Yes
Instructions:
1. Download firmware version 2.8 or newer from Schneider Electric's website. 2. Follow the firmware update procedure in the Easergy T300 user manual. 3. Verify the firmware version after update. 4. Test device functionality.
🔧 Temporary Workarounds
Network Segmentation
allIsolate Easergy T300 devices in dedicated network segments with strict firewall rules.
Access Control Lists
allImplement IP-based access restrictions to limit communication to authorized management stations only.
🧯 If You Can't Patch
- Implement strict network segmentation with firewall rules blocking all unnecessary traffic to affected devices
- Deploy network monitoring and intrusion detection specifically for industrial control system protocols
🔍 How to Verify
Check if Vulnerable:
Check firmware version via device web interface or Schneider Electric configuration tools. If version is 2.7 or older, device is vulnerable.Check Version:
Use Schneider Electric's configuration software or access the device web interface to view firmware version.Verify Fix Applied:
After updating, verify firmware version shows 2.8 or newer and test that authentication is required for all critical functions.📡 Detection & Monitoring
Log Indicators:
- Unauthenticated access attempts to device management interfaces
- Configuration changes without proper authentication logs
- Unusual command execution patterns
Network Indicators:
- Unusual traffic patterns to Easergy T300 web ports (typically 80/443)
- Industrial protocol traffic from unauthorized sources
- Multiple failed authentication attempts followed by successful access
SIEM Query:
source_ip NOT IN authorized_management_ips AND dest_port IN (80,443) AND dest_ip IN easergy_devices