Easy Level:

Basic System Understanding: Familiarity with operating systems, file structures, and basic command-line interfaces.

Introduction to Network Concepts: Understanding of basic networking concepts such as IP addresses, DNS, and routing.

Basic Cryptography: Awareness of fundamental concepts of encryption and hashing.

Scripting and Automation: Introduction to scripting (e.g., Python, Bash) for automating simple tasks.

Web Fundamentals: Understanding of how web applications work, including client-server architecture.

Medium Level:

Intermediate System Administration: Deeper understanding of system internals, user and group management, and system monitoring.

Network Traffic Analysis: Ability to use tools to capture and analyze network traffic, identifying suspicious activities.

Intermediate Cryptography: Understanding of more complex cryptographic systems and public key infrastructure.

Reverse Engineering Basics: Introduction to reverse engineering tools and techniques for analyzing binary files.

Web Application Security: Understanding of common web vulnerabilities and experience in exploiting them safely and ethically.

Hard Level:

Advanced System Exploitation: Knowledge of advanced exploitation techniques such as buffer overflows, ROP chains, and shellcode development.

Complex Network Intrusions: Ability to understand and carry out sophisticated network intrusions, bypassing advanced security mechanisms.

Advanced Cryptanalysis: Skills in attacking cryptographic systems, understanding encryption weaknesses and side-channel attacks.

Forensic and Incident Response: Ability to perform forensic analysis on compromised systems and understand the steps for effective incident response.

Advanced Web and Application Security: Deep understanding of complex web application vulnerabilities and experience in writing custom exploits.