Book Image

Certified Ethical Hacker (CEH) v12 312-50 Exam Guide

By : Dale Meredith
Book Image

Certified Ethical Hacker (CEH) v12 312-50 Exam Guide

By: Dale Meredith

Overview of this book

With cyber threats continually evolving, understanding the trends and using the tools deployed by attackers to determine vulnerabilities in your system can help secure your applications, networks, and devices. To outmatch attacks, developing an attacker's mindset is a necessary skill, which you can hone with the help of this cybersecurity book. This study guide takes a step-by-step approach to helping you cover all the exam objectives using plenty of examples and hands-on activities. You'll start by gaining insights into the different elements of InfoSec and a thorough understanding of ethical hacking terms and concepts. You'll then learn about various vectors, including network-based vectors, software-based vectors, mobile devices, wireless networks, and IoT devices. The book also explores attacks on emerging technologies such as the cloud, IoT, web apps, and servers and examines prominent tools and techniques used by hackers. Finally, you'll be ready to take mock tests, which will help you test your understanding of all the topics covered in the book. By the end of this book, you'll have obtained the information necessary to take the 312-50 exam and become a CEH v11 certified ethical hacker.
Table of Contents (23 chapters)
1
Section 1: Where Every Hacker Starts
10
Section 2: A Plethora of Attack Vectors
15
Section 3: Cloud, Apps, and IoT Attacks
20
Chapter 17: CEH Exam Practice Questions

Enumerating using SMTP

Who would think a simple protocol that we use in day-to-day life, such as SMTP, could reveal so much about a network? A famous T-shirt went around at Blackhat several years ago. Most people didn't understand the meaning. It simply said I read your email.:

Figure 5.4 – I read your email T-shirt from Blackhat

That's so true. Normally, email is transmitted in clear text, meaning that messages are readable. As email servers communicate with each other, they also transmit information via the SMTP protocol, which can be used to further enumerate your network.

The purpose of this is not necessarily to read people's emails, even though that could give up a lot of information. It's more about looking at what we refer to as the headers of the email, which is the information that gets attached to the beginning of the email during transit, which exposes quite a bit.

So, what is SMTP? It's simply a protocol we...