Hello. This is Creative. First of all, I apologize for the inconvenience. You said, "I omitted the explanation to lead you to another lecture." But I really did not intend to do that. Since hacking and vulnerabilities are interrelated, there are many cases where a lecture on vulnerability A is related to vulnerability B. This lecture is especially related to the authentication mechanism, so there are many cases where attacks are carried out by linking it to other vulnerabilities, so I think you will feel that way even more. However, I cannot explain the concept and principle of the vulnerability in every lecture... I have over 10 lectures, and I cannot explain the concept of the vulnerability in every lecture. Then, it is natural that students who have already taken the lecture will feel tired and uncomfortable. Also, I do not want to increase the time by explaining other vulnerabilities in an already long lecture. I ask for your generous understanding in this regard. Thank you.