What is the primary goal of cryptanalysis?

To break or weaken cryptographic systems

To design new cryptographic algorithms

To manage cryptographic keys securely

To implement cryptographic protocols

Which scenario is an example of a chosen-plaintext attack?

An attacker has a known plaintext-ciphertext pair from a previous communication

An attacker intercepts ciphertext and uses frequency analysis

An attacker sends chosen ciphertexts to a decryption oracle

An attacker submits crafted messages to an encryption service and observes the outputs

What is the primary action in a man-in-the-middle (MITM) attack?

Capturing and replaying a valid transmission later

Intercepting and potentially altering communication between two parties

Analyzing the frequency of characters in ciphertext

Using a precomputed list of passwords

How can a man-in-the-middle attack break a cryptographic protocol?

By using a rainbow table to reverse hashes

By impersonating each party to the other and negotiating separate keys

By trying all possible keys until one works

By measuring the power consumption of the encryption device

Why is a dictionary attack often successful against systems that use simple passwords?

Because simple passwords are often found in common wordlists

Because it tries every possible key combination

Because it uses rainbow tables to reverse hashes

Because it exploits timing differences in password verification

EC-CouncilCertified Ethical Hacker

Domain 9Objective 3

Cryptanalysis and Attacks CEH Practice Questions (Page 10)

Part of the Cryptography domain, which makes up ~9% of our current practice bank. EC-Council does not publish an official question count, but from its 240-minute exam (~95–160 total, ~9–14 in this domain), expect 2–4 from this objective — we provide 63 practice questions to prepare you well beyond it. (estimate)

63questions here

13free pages

16concepts

16 Concepts in This Objective

Cryptanalysis Fundamentals
Types of Cryptanalytic Attacks
Brute-Force Attack
Dictionary Attack
Rainbow Table Attack
Frequency Analysis
Known-Plaintext Attack
Chosen-Plaintext Attack
Chosen-Ciphertext Attack
Related-Key Attack
Side-Channel Attacks
Man-in-the-Middle Attack
Replay Attack
Birthday Attack
Meet-in-the-Middle Attack
Cryptanalytic Tools and Techniques

Questions 46–50

46foundation · easy
What is the primary goal of cryptanalysis?
Select an answer first
47foundation · easy
Which scenario is an example of a chosen-plaintext attack?
Select an answer first
48foundation · easy
What is the primary action in a man-in-the-middle (MITM) attack?
Select an answer first
49foundation · easy
How can a man-in-the-middle attack break a cryptographic protocol?
Select an answer first
50foundation · easy
Why is a dictionary attack often successful against systems that use simple passwords?
Select an answer first

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