CVE-2021-27451
📋 TL;DR
Mesa Labs AmegaView versions 3.0 and prior use a weak passcode generation algorithm that can be easily reversed, allowing attackers to calculate valid passcodes and gain unauthorized access to the device. This affects industrial control systems using these specific versions of the AmegaView software.
💻 Affected Systems
- Mesa Labs AmegaView
📦 What is this software?
Amegaview by Mesalabs
⚠️ Risk & Real-World Impact
Worst Case
An attacker gains full administrative access to the AmegaView device, potentially compromising connected industrial control systems, manipulating critical parameters, or disrupting operations.
Likely Case
Unauthorized users gain access to device configuration and monitoring functions, potentially altering settings or viewing sensitive operational data.
If Mitigated
With proper network segmentation and access controls, impact is limited to the specific device without affecting broader industrial control systems.
🎯 Exploit Status
The vulnerability involves a weak algorithm that can be reversed to generate valid passcodes, requiring some knowledge of the algorithm but minimal technical skill.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Version 3.1 or later
Vendor Advisory: https://us-cert.cisa.gov/ics/advisories/icsa-21-147-03
Restart Required: Yes
Instructions:
1. Download the latest version from Mesa Labs. 2. Install the update following vendor instructions. 3. Restart the AmegaView application. 4. Verify the new version is running.
🔧 Temporary Workarounds
Network Segmentation
allIsolate AmegaView devices on separate network segments with strict firewall rules to limit access.
Access Control Lists
allImplement strict IP-based access controls to limit which systems can connect to AmegaView devices.
🧯 If You Can't Patch
- Implement network segmentation to isolate vulnerable devices from critical systems
- Enable detailed logging and monitoring for unauthorized access attempts
🔍 How to Verify
Check if Vulnerable:
Check the AmegaView software version in the application's About or Help menu. If version is 3.0 or earlier, the system is vulnerable.Check Version:
Check version through AmegaView application interface (no CLI command available)Verify Fix Applied:
After updating, verify the version shows 3.1 or later in the application's About or Help menu.📡 Detection & Monitoring
Log Indicators:
- Multiple failed login attempts followed by successful login
- Login attempts from unusual IP addresses
- Configuration changes from unexpected sources
Network Indicators:
- Unexpected connections to AmegaView ports
- Traffic patterns indicating brute force attempts
SIEM Query:
source="amegaview" AND (event_type="login" OR event_type="auth") AND result="success" | stats count by src_ip