Book Image

Practical Linux Security Cookbook - Second Edition

By : Tajinder Kalsi
Book Image

Practical Linux Security Cookbook - Second Edition

By: Tajinder Kalsi

Overview of this book

Over the last few years, system security has gained a lot of momentum and software professionals are focusing heavily on it. Linux is often treated as a highly secure operating system. However, the reality is that Linux has its share of security ?aws, and these security ?aws allow attackers to get into your system and modify or even destroy your important data. But there’s no need to panic, since there are various mechanisms by which these ?aws can be removed, and this book will help you learn about different types of Linux security to create a more secure Linux system. With a step-by-step recipe approach, the book starts by introducing you to various threats to Linux systems. Then, this book will walk you through customizing the Linux kernel and securing local files. Next, you will move on to managing user authentication both locally and remotely and mitigating network attacks. Later, you will learn about application security and kernel vulnerabilities. You will also learn about patching Bash vulnerability, packet filtering, handling incidents, and monitoring system logs. Finally, you will learn about auditing using system services and performing vulnerability scanning on Linux. By the end of this book, you will be able to secure your Linux systems and create a robust environment.
Table of Contents (20 chapters)
Title Page
Copyright and Credits
Contributors
Packt Upsell
Preface
Index

OSSEC


As a system administrator, we may want to keep track of authorized and unauthorized activity on your server. OSSEC may be the solution for this. It's an open source host-based intrusion detection system, which can be used for tracking server activity. When properly configured, OSSEC can perform log analysis, integrity checking, rootkit detection, time-based alerting, and many other things.

Getting ready

To install and configure OSSEC, we will use an Ubuntu server. Additional packages such as gcc, libc, Apache, and PHP may be needed for compiling and running OSSEC. Also, if we want real-time alerting to work, a separate package would be needed for this. To install all the essential packages, run the command shown here:

How to do it...

In this section, we will learn how OSSEC can be installed and configured to monitor a local Ubuntu server. We will also test OSSEC against any file modifications:

  1. Our first step will be to download the latest version of OSSEC from its GitHub repository using...