Book Image

Mastering Linux Security and Hardening - Third Edition

By : Donald A. Tevault
3.7 (7)
Book Image

Mastering Linux Security and Hardening - Third Edition

3.7 (7)
By: Donald A. Tevault

Overview of this book

The third edition of Mastering Linux Security and Hardening is an updated, comprehensive introduction to implementing the latest Linux security measures, using the latest versions of Ubuntu and AlmaLinux. In this new edition, you will learn how to set up a practice lab, create user accounts with appropriate privilege levels, protect sensitive data with permissions settings and encryption, and configure a firewall with the newest firewall technologies. You’ll also explore how to use sudo to set up administrative accounts with only the privileges required to do a specific job, and you’ll get a peek at the new sudo features that have been added over the past couple of years. You’ll also see updated information on how to set up a local certificate authority for both Ubuntu and AlmaLinux, as well as how to automate system auditing. Other important skills that you’ll learn include how to automatically harden systems with OpenSCAP, audit systems with auditd, harden the Linux kernel configuration, protect your systems from malware, and perform vulnerability scans of your systems. As a bonus, you’ll see how to use Security Onion to set up an Intrusion Detection System. By the end of this new edition, you will confidently be able to set up a Linux server that will be secure and harder for malicious actors to compromise.
Table of Contents (22 chapters)
1
Section 1: Setting up a Secure Linux System
9
Section 2: Mastering File and Directory Access Control (DAC)
12
Section 3: Advanced System Hardening Techniques
20
Other Books You May Enjoy
21
Index

Scanning for rootkits with Rootkit Hunter

Rootkits are exceedingly nasty pieces of malware that can definitely ruin your day. They can listen for commands from their masters, steal sensitive data and send it to their masters, or provide an easy-access back door for their masters. They’re designed to be stealthy, with the ability to hide themselves from plain view. Sometimes, they’ll replace utilities such as ls or ps with their own trojaned versions that will show all files or processes on the system except for the ones that are associated with the rootkit. Rootkits can infect any operating system, even our beloved Linux.

In order to plant a rootkit, an attacker has to have already gained administrative privileges on a system. This is one of the many reasons why I always cringe when I see people doing all of their work from the root user’s shell and why I’m a firm advocate of using sudo whenever possible. I mean, really, why should we make it easy for...