Kevin, an encryption specialist, implemented a technique that enhances the security of keys used for...

The scenario describes a method used to make a cryptographic key more secure by making it harder to brute-force. This process is called Key Stretching.

Key Stretching:

Takes a weak or short key and processes it through a function (often repeatedly) to produce a stronger, longer key.

Commonly used in password hashing (e.g., bcrypt, PBKDF2, scrypt).

Increases the computational time required to test each guess in a brute-force attack, effectively reducing attack feasibility.

Incorrect Options:

A. Key derivation function (KDF) is related but more general; key stretching is a specific technique often implemented within KDFs.

B. Key reinstallation is associated with WPA2 KRACK attacks.

C. Public key infrastructure (PKI) is a system of digital certificates, not a key strengthening technique.

Reference – CEH v13 Official Courseware:

Module 20: Cryptography

Section: “Password Hashing and Key Stretching Techniques”

Subsection: “bcrypt, PBKDF2, and Key Strengthening”

CEH iLab: Password Hashing and Cracking Simulations