What is the primary goal of using an ACK scan in the context of firewall evasion?

To map firewall rules by determining which ports are filtered or unfiltered.

To fragment packets to bypass packet filters.

To evade IDS by using a random source IP address.

To establish a full TCP connection and identify open ports.

Which technique is commonly used to bypass a firewall that only allows inbound TCP connections on port 80 and 443?

Using an ACK scan to determine firewall rules.

Using a NULL scan to avoid setting any flags.

Using a source port of 80 or 443 for the scan packets.

Using a UDP scan to avoid TCP filtering.

EC-CouncilCertified Ethical Hacker

Domain 2Objective 4

Port Scanning Techniques CEH Practice Questions (Page 4)

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 16–20

16foundation · easy
Which technique involves splitting a port scan packet into smaller fragments to evade detection by network security devices?
Select an answer first
17foundation · easy
What is the primary goal of using an ACK scan in the context of firewall evasion?
Select an answer first
18expert · hard
A penetration tester is conducting a port scan of a target network that has an IDS that can detect port scans by correlating traffic from a single source IP. The tester wants to avoid detection while also obtaining accurate results. The tester has a limited amount of time and cannot use a slow scan. Which Nmap option is most appropriate?
Select an answer first
19application · medium
A network administrator is troubleshooting a firewall rule that is blocking a legitimate application. The administrator wants to determine whether the firewall is dropping packets or the application is not listening on the expected port. Which Nmap scan should the administrator use to differentiate between a filtered port and a closed port?
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20foundation · easy
Which technique is commonly used to bypass a firewall that only allows inbound TCP connections on port 80 and 443?
Select an answer first

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Port Scanning Techniques CEH Practice Questions (Page 4)

Questions 16–20

Which technique involves splitting a port scan packet into smaller fragments to evade detection by network security devices?

What is the primary goal of using an ACK scan in the context of firewall evasion?

Which technique is commonly used to bypass a firewall that only allows inbound TCP connections on port 80 and 443?

Keep studying — Reconnaissance Techniques