Crucial Exams

Certified Ethical Hacker (CEH) Practice Question

During a penetration test of a manufacturing plant's OT network, you confirm that several programmable logic controllers communicate with the SCADA server over Modbus/TCP. To gather vendor, firmware, and device identification with minimal risk of disrupting operations, which Nmap command-line approach should you use, and on which default port will the probe be sent?

  • Execute nmap -sS --script enip-info -p 44818 <target> to probe the controller's EtherNet/IP service.

  • Execute nmap -sU --script dnp3-enum-enip -p 20000 <target> to enumerate devices over DNP3 on UDP port 20000.

  • Execute nmap -sV --script modbus-discover -p 502 <target> to query the Modbus service on its default port 502.

  • Run nmap -A -p- <target> to aggressively scan every TCP port for possible Modbus endpoints.

Certified Ethical Hacker (CEH)
Mobile Platform, IoT, and OT Hacking
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