CVE-2021-38419
📋 TL;DR
This vulnerability in Fuji Electric V-Server Lite and Tellus Lite V-Simulator allows attackers to write data beyond allocated memory boundaries, potentially leading to system crashes, data corruption, or remote code execution. It affects industrial control systems using these software products for monitoring and simulation. Organizations using these systems in industrial environments are at risk.
💻 Affected Systems
- Fuji Electric V-Server Lite
- Fuji Electric Tellus Lite V-Simulator
📦 What is this software?
V Server by Fujielectric
V Simulator by Fujielectric
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete system compromise, manipulation of industrial processes, or disruption of critical operations.
Likely Case
System crashes or data corruption causing operational disruption in industrial environments.
If Mitigated
Limited impact if systems are isolated and have proper network segmentation.
🎯 Exploit Status
Out-of-bounds write vulnerabilities typically require some understanding of memory layout but can be exploited remotely without authentication.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: v4.0.12.0
Vendor Advisory: https://www.cisa.gov/uscert/ics/advisories/icsa-21-299-01
Restart Required: Yes
Instructions:
1. Download v4.0.12.0 or later from Fuji Electric. 2. Backup current configuration and data. 3. Install the update following vendor instructions. 4. Restart the system. 5. Verify the update was successful.
🔧 Temporary Workarounds
Network Segmentation
allIsolate affected systems from untrusted networks and implement strict firewall rules.
Access Control
allImplement strict access controls and authentication mechanisms for these systems.
🧯 If You Can't Patch
- Implement strict network segmentation to isolate affected systems from untrusted networks.
- Monitor for unusual system behavior, crashes, or unexpected network connections.
🔍 How to Verify
Check if Vulnerable:
Check software version in application interface or Windows Programs and Features. If version is below 4.0.12.0, system is vulnerable.Check Version:
Check application 'About' dialog or Windows Control Panel > Programs and FeaturesVerify Fix Applied:
Verify version number shows 4.0.12.0 or higher in application interface or Windows Programs and Features.📡 Detection & Monitoring
Log Indicators:
- Application crashes
- Unexpected termination of V-Server Lite or V-Simulator processes
- Memory access violation errors
Network Indicators:
- Unexpected network connections to/from affected systems
- Traffic patterns inconsistent with normal industrial operations
SIEM Query:
source="windows" AND (event_id=1000 OR event_id=1001) AND process_name="V-Server*" OR process_name="V-Simulator*"