CVE-2021-38401
📋 TL;DR
This vulnerability in Fuji Electric V-Server Lite and Tellus Lite V-Simulator allows attackers to execute arbitrary code by exploiting an untrusted pointer dereference. It affects industrial control system software used in manufacturing and automation environments. Successful exploitation could lead to complete system compromise.
💻 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
Full system compromise allowing attacker to execute arbitrary code, crash critical industrial control systems, and potentially disrupt manufacturing operations or cause physical damage.
Likely Case
Application crash leading to denial of service in industrial environments, potentially disrupting monitoring and control functions.
If Mitigated
Limited impact if systems are isolated from untrusted networks and proper access controls are implemented.
🎯 Exploit Status
The vulnerability requires network access to the affected software but does not require 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 the patched version v4.0.12.0 from Fuji Electric. 2. Backup current configuration and data. 3. Install the update following vendor instructions. 4. Restart the application and verify functionality.
🔧 Temporary Workarounds
Network Segmentation
allIsolate affected systems from untrusted networks and implement strict firewall rules.
Access Control Restrictions
allImplement strict network access controls to limit connections to trusted sources only.
🧯 If You Can't Patch
- Implement strict network segmentation to isolate affected systems from untrusted networks
- Deploy intrusion detection systems to monitor for exploitation attempts
🔍 How to Verify
Check if Vulnerable:
Check the software version in the application's About or Help menu. If version is below 4.0.12.0, the system is vulnerable.Check Version:
Check application version through GUI or consult vendor documentation for version verification.Verify Fix Applied:
Verify the software version shows 4.0.12.0 or higher after patching.📡 Detection & Monitoring
Log Indicators:
- Application crash logs
- Unexpected process termination
- Memory access violation errors
Network Indicators:
- Unexpected network connections to the V-Server/Tellus Lite ports
- Malformed packets targeting the application
SIEM Query:
source="application_logs" AND ("V-Server" OR "Tellus Lite") AND ("crash" OR "access violation" OR "memory error")