Book Image

Mastering Linux Security and Hardening

By : Donald A. Tevault
Book Image

Mastering Linux Security and Hardening

By: Donald A. Tevault

Overview of this book

This book has extensive coverage of techniques that will help prevent attackers from breaching your system, by building a much more secure Linux environment. You will learn various security techniques such as SSH hardening, network service detection, setting up firewalls, encrypting file systems, protecting user accounts, authentication processes, and so on. Moving forward, you will also develop hands-on skills with advanced Linux permissions, access control, special modes, and more. Lastly, this book will also cover best practices and troubleshooting techniques to get your work done efficiently. By the end of this book, you will be confident in delivering a system that will be much harder to compromise.
Table of Contents (15 chapters)
Title Page
Packt Upsell
Contributors
Preface

Creating and managing keys for password-less logins


The Secure Shell Suite, or SSH, is a great set of tools that provides secure, encrypted communications with remote servers. You can use the SSH component to remotely log into the command-line of a remote machine, and you can use either scp or sftp to securely transfer files. The default way to use any of these SSH components is to use the username and password of a person's normal Linux user account. So, logging into a remote machine from the terminal of my OpenSUSE workstation would look something like:

donnie@linux-0ro8:~> ssh [email protected]
[email protected]'s password:

While it's true that the username and password go across the network in an encrypted format, making it hard for malicious actors to intercept, it's still not the most secure way of doing business. The problem is that attackers have access to automated tools that can perform brute-force password attacks against an SSH server. Botnets, such as the Hail Mary Cloud...