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

Prevent Unwanted Programs from Running

Once upon a time, we didn’t have to worry much about Linux malware. While it’s still true that Linux users don’t have to worry about viruses, there are other types of malware that can definitely ruin a Linux user’s day. Cryptomining programs planted on your server can eat up memory and CPU cycles, causing your server to work much harder and use more power than it should. Ransomware, which can encrypt either important files or a system’s bootloader, can make these important files or even the whole system inaccessible. Even paying the demanded ransom isn’t always a guarantee that your system will be returned to proper order. One way to prevent these programs from doing their damage is to only allow authorized programs to run, and to block everything else. We have two ways of doing that, which are the topics of this chapter:

  • Mount partitions with the no options
  • Use fapolicyd on Red Hat-type...