Book Image

Mastering Linux Security and Hardening - Second Edition

By : Donald A. Tevault
Book Image

Mastering Linux Security and Hardening - Second Edition

By: Donald A. Tevault

Overview of this book

From creating networks and servers to automating the entire working environment, Linux has been extremely popular with system administrators for the last couple of decades. However, security has always been a major concern. With limited resources available in the Linux security domain, this book will be an invaluable guide in helping you get your Linux systems properly secured. Complete with in-depth explanations of essential concepts, practical examples, and self-assessment questions, this book begins by helping you set up a practice lab environment and takes you through the core functionalities of securing Linux. You'll practice various Linux hardening techniques and advance to setting up a locked-down Linux server. As you progress, you will also learn how to create user accounts with appropriate privilege levels, protect sensitive data by setting permissions and encryption, and configure a firewall. The book will help you set up mandatory access control, system auditing, security profiles, and kernel hardening, and finally cover best practices and troubleshooting techniques to secure your Linux environment efficiently. By the end of this Linux security book, you will be able to confidently set up a Linux server that will be much harder for malicious actors to compromise.
Table of Contents (20 chapters)
1
Section 1: Setting up a Secure Linux System
8
Section 2: Mastering File and Directory Access Control (DAC)
11
Section 3: Advanced System Hardening Techniques

Setting up a chroot environment for SFTP users

Secure File Transfer Protocol (SFTP) is a great tool for performing secure file transfers. There is a command-line client, but users will most likely use a graphical client, such as FileZilla. A website owners to upload web content files to the proper content directories on a web server. With a default SSH setup, anyone who has a user account on a Linux machine can log in through either SSH or SFTP and can navigate through the server's entire filesystem. What we really want for SFTP users is to prevent them from logging into a command prompt via SSH, and to confine them to their own designated directories.

Creating a group and configuring the sshd_config file

With the exception...