Key FeaturesDiscover security techniques to prevent malware from infecting a Linux system, and detect itPrevent unauthorized people from breaking into a Linux systemProtect important and sensitive data from being revealed to unauthorized personsBook DescriptionThe 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.What you will learnPrevent malicious actors from compromising a production Linux systemLeverage additional features and capabilities of Linux in this new versionUse locked-down home directories and strong passwords to create user accountsPrevent unauthorized people from breaking into a Linux systemConfigure file and directory permissions to protect sensitive dataHarden the Secure Shell service in order to prevent break-ins and data lossApply security templates and set up auditingWho this book is forThis book is for Linux administrators, system administrators, and network engineers interested in securing moderate to complex Linux environments. Security consultants looking to enhance their Linux security skills will also find this book useful. Working experience with the Linux command line and package management is necessary to understand the concepts covered in this book.About the AuthorDonald A. Tevault - but you can call him Donnie - got involved with Linux way back in 2006, and has been working with it ever since. He holds the Linux Professional Institute Level 3-Security certification, and the GIAC Incident Handler certification. Donnie is a professional Linux trainer, and thanks to the magic of the internet, teaches Linux classes literally the world over from the comfort of his living room. He's also a Linux security researcher for an IoT security company. Table of ContentsRunning Linux in a Virtual EnvironmentSecuring Administrative User AccountsSecuring Normal User AccountsSecuring Your Server with a Firewall - Part 1Securing Your Server with a Firewall - Part 2Encryption TechnologiesSSH HardeningMastering Discretionary Access ControlAccess Control Lists and Shared Directory ManagementImplementing Mandatory Access Control with SELinux and AppArmorKernel Hardening and Process IsolationScanning, Auditing and HardeningLogging and Log SecurityVulnerability Scanning and Intrusion DetectionPrevent Unwanted Programs from RunningSecurity Tips & Tricks for the Busy Bee