Certified Ethical Hacker Network Security and Scanning

Question 1

What is the purpose of a SYN scan (half-open scan) in network reconnaissance?

Accepted Answer

To identify open ports without completing the TCP handshake, making it stealthier

Answer

A SYN scan sends SYN packets and analyzes responses (SYN-ACK = open, RST = closed) without completing the three-way handshake, making it faster and harder to detect than full connect scans.

Question 2

What is the difference between active and passive reconnaissance?

Accepted Answer

Active directly interacts with the target system; passive gathers information without direct contact

Answer

Active reconnaissance involves direct interaction with the target (port scanning, vulnerability scanning), while passive reconnaissance gathers publicly available information (WHOIS, social media, DNS records) without alerting the target.

Question 3

What is OS fingerprinting in ethical hacking?

Accepted Answer

Identifying the target's operating system by analyzing network packet characteristics

Answer

OS fingerprinting analyzes unique characteristics of network packets (TTL values, TCP window size, DF bit) to identify the target's operating system and version, using tools like Nmap.

Question 4

What is a vulnerability assessment versus a penetration test?

Accepted Answer

VA identifies vulnerabilities without exploitation; a pentest actively exploits vulnerabilities to prove impact

Answer

A vulnerability assessment scans and identifies potential security weaknesses, while a penetration test goes further by actively attempting to exploit discovered vulnerabilities to demonstrate real-world impact.

Question 5

What is banner grabbing and what information does it reveal?

Accepted Answer

Connecting to services to capture their version information and software details

Answer

Banner grabbing connects to network services (HTTP, FTP, SMTP) and captures the service banner which typically reveals the software name, version, and sometimes OS information, helping identify exploitable vulnerabilities.

Certified Ethical Hacker Practice Test

Certified Ethical Hacker Practice Test

Certified Ethical Hacker Network Security and Scanning