Which defensive measure is specifically designed to detect port scanning activities on a network?

Using strong passwords and multi-factor authentication on all systems.

Deploying an intrusion detection system (IDS) that monitors for unusual connection attempts.

Regularly updating antivirus software on all endpoints.

Encrypting all network traffic with VPNs.

An ethical hacker is scanning a target network that has an intrusion detection system (IDS) configured to alert on sequential port scans from a single source IP. The hacker wants to avoid triggering the IDS while still gathering information about open ports. Which Nmap technique should the hacker use?

Use the -D option with decoy IP addresses

Use the -sV option to enable version detection

Use the -T5 timing template to speed up the scan

Use the -O option to enable OS detection

A penetration tester is scanning a target that is protected by an intrusion prevention system (IPS) that drops packets with the 'don't fragment' bit set. The tester wants to evade the IPS while performing a SYN scan. Which Nmap option should the tester use?

-mtu 8 (set the MTU to 8 bytes)

EC-CouncilCertified Ethical Hacker

Domain 2Objective 4

Port Scanning Techniques CEH Practice Questions (Page 6)

Part of the Reconnaissance Techniques domain, which makes up ~14% of our current practice bank. EC-Council does not publish an official question count, but from its 240-minute exam (~95–160 total, ~13–22 in this domain), expect 2–3 from this objective — we provide 43 practice questions to prepare you well beyond it. (estimate)

43questions here

9free pages

7concepts

Questions 26–30

26application · medium
An ethical hacker is performing a port scan against a target that has an IDS configured to alert on any TCP packet with the SYN flag set. The hacker wants to avoid triggering the IDS while still identifying open TCP ports. Which Nmap scan type should be used?
Select an answer first
27foundation · easy
Which defensive measure is specifically designed to detect port scanning activities on a network?
Select an answer first
28application · medium
A security tester is scanning a target that is behind a firewall that drops all inbound packets that are not part of an established connection. The tester wants to identify open ports on the target. Which Nmap option should be used to bypass this firewall?
Select an answer first
29application · medium
An ethical hacker is scanning a target network that has an intrusion detection system (IDS) configured to alert on sequential port scans from a single source IP. The hacker wants to avoid triggering the IDS while still gathering information about open ports. Which Nmap technique should the hacker use?
Select an answer first
30application · medium
A penetration tester is scanning a target that is protected by an intrusion prevention system (IPS) that drops packets with the 'don't fragment' bit set. The tester wants to evade the IPS while performing a SYN scan. Which Nmap option should the tester use?
Select an answer first

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Port Scanning Techniques CEH Practice Questions (Page 6)

Questions 26–30

An ethical hacker is performing a port scan against a target that has an IDS configured to alert on any TCP packet with the SYN flag set. The hacker wants to avoid triggering the IDS while still identifying open TCP ports. Which Nmap scan type should be used?

Which defensive measure is specifically designed to detect port scanning activities on a network?

A security tester is scanning a target that is behind a firewall that drops all inbound packets that are not part of an established connection. The tester wants to identify open ports on the target. Which Nmap option should be used to bypass this firewall?

A penetration tester is scanning a target that is protected by an intrusion prevention system (IPS) that drops packets with the 'don't fragment' bit set. The tester wants to evade the IPS while performing a SYN scan. Which Nmap option should the tester use?

Keep studying — Reconnaissance Techniques