Book Image

Hands-On Penetration Testing with Kali NetHunter

By : Glen D. Singh, Sean-Philip Oriyano
Book Image

Hands-On Penetration Testing with Kali NetHunter

By: Glen D. Singh, Sean-Philip Oriyano

Overview of this book

Kali NetHunter is a version of the popular and powerful Kali Linux pentesting platform, designed to be installed on mobile devices. Hands-On Penetration Testing with Kali NetHunter will teach you the components of NetHunter and how to install the software. You’ll also learn about the different tools included and how to optimize and use a package, obtain desired results, perform tests, and make your environment more secure. Starting with an introduction to Kali NetHunter, you will delve into different phases of the pentesting process. This book will show you how to build your penetration testing environment and set up your lab. You will gain insight into gathering intellectual data, exploiting vulnerable areas, and gaining control over target systems. As you progress through the book, you will explore the NetHunter tools available for exploiting wired and wireless devices. You will work through new ways to deploy existing tools designed to reduce the chances of detection. In the concluding chapters, you will discover tips and best practices for integrating security hardening into your Android ecosystem. By the end of this book, you will have learned to successfully use a mobile penetration testing device based on Kali NetHunter and Android to accomplish the same tasks you would traditionally, but in a smaller and more mobile form factor.
Table of Contents (19 chapters)
Title Page
Copyright and Credits
About Packt
Contributors
Preface
Index

Enumerating SMTP


SMTP is a protocol used to transfer messages and is commonly used in both mail servers and mail clients. The simplicity and reliability of the protocol has led to its widespread adoption and a handful of revisions since it was first introduced way back in 1982.

SMTP, in the context of a messaging system, is used two different ways. In the case of mail servers, the protocol is used to transfer messages from one server to another until it reaches the server where the recipient's mailbox is located where it is  stored for later retrieval. On the mail client side, the protocol is used to send messages to a mail server and make use of other protocols for retrieving messages from the server.

For pentesters, SMTP can represent a valuable source of information, in particular, user names and email addresses. The technique we will use here is designed to query an SMTP service and retrieve usernames along with domain names. You may not consciously think about it, but you see this information...