Hacking as a hobby #4 (Nebula)

You now have more freedom in cyberspace than ever before.

If you've ever been fascinated by people typing in unknown Linux commands on a black screen, but were at a loss as to where to start or what to do, this course is for you.

You can clear all the challenges of the international hacking competition SquareCTF (2018~2019). Broaden your senses and perspectives on IT and security by experiencing various challenges!

You can clear all the challenges of the hacking competition SquareCTF (2017).

Episodes from the year I started from scratch to stand on my own after quitting my dream job.

You can clear all preliminary challenges of the hacking competition DIMICTF (2019).

Covering the content of WebGoat, the classic wargame of web hacking, we have translated and solved all the lessons and challenges from beginning to end. We provide all the tools and data needed to solve the challenges, starting with setting up the practice environment.

This is a free special lecture that can help you strengthen your information security and personal information protection capabilities.

If you've ever been fascinated by people typing in unknown Linux commands on a black screen, but were at a loss as to where to start or what to do, this course is for you.

You can clear all the challenges of the hacking competition SquareCTF (2017).

Want to work for a long time as a super developer who can handle the entire process of service development and operation on your own? Then build a solid foundation in IT infrastructure knowledge from the ground up, which is just as important as various development languages!

IT services are rapidly transitioning to cloud environments. You will learn security practices from basic virtual infrastructure construction to security threat monitoring and vulnerability diagnosis for each area to secure the Amazon AWS cloud environment.

This course is for those who want to develop packet analysis programs like Wireshark and various network solutions using the Npcap library.

This training will help you understand the world-famous cloud, build your own cloud environment, and strengthen your ability to use it easily.

This lecture provides a general guide on how to prepare while studying when you want to choose a career in IT security penetration testing, and what questions and answers to prepare for the interview. I will share my experience working as a penetration testing consultant, at large companies, and in the financial sector, and currently running a penetration testing consulting business.

This lecture guides those who have learned the basic course of network core theory by memorizing it to understand theories in more depth. It covers more in-depth theories such as NAT technology, the operating principle of Internet routers, load distribution system principles, and VPN technology principles. The goal of this lecture is also to finish it by memorizing it! You can do it!

Learn about networks easily, quickly, and engagingly with pictures and videos!

Master AWS networking completely! Learn VPC, subnet, routing, and security with a focus on practical application, and design secure and scalable cloud network architectures. Complete the core skills that every working engineer must know in a short period of time!

Incident response is less about mastering tools and more about knowing what to judge first. Rather than focusing on how to analyze malware, this course explains the realistic thought process of determining **"whether the current situation is an actual incident and what actions to take first."** Using webtoon-based real-world scenarios, we have organized the entire flow of incident response—from identifying signs of intrusion to incident assessment, initial response, containment, and analysis/forensics—in a way that even non-experts can understand. This is not just a collection of fragmented technical explanations; it is a course where you learn the decision-making criteria and response perspectives that practitioners can apply immediately in the field.

This is a course where you can learn the basics of web technology. You can learn the basics of web technology in a short period of time. If you are interested in studying or getting a job related to the web, you must take this course!