Linux Server Security

A concise but comprehensive guide to providing the best possible security for a server, with examples and background to help you understand the issues involved. For each of the tasks or services covered, this book lays out the reasons for security, the risks and needs involved, the background to understand the solutions, and step by step guidelines for doing the job.

Learn how to attack and defend the world’s most popular web server platform Linux Server Security: Hack and Defend presents a detailed guide for experienced admins, aspiring hackers and other IT professionals seeking a more advanced understanding of Linux security. Written by a 20-year veteran of Linux server deployment this book provides the insight of experience along with highly practical instruction. The topics range from the theory of past, current, and future attacks, to the mitigation of a variety of online attacks, all the way to empowering you to perform numerous malicious attacks yourself (in the hope that you will learn how to defend against them). By increasing your understanding of a hacker’s tools and mindset you're less likely to be confronted by the all-too-common reality faced by many admins these days: someone else has control of your systems. Master hacking tools and launch sophisticated attacks: perform SQL injections, deploy multiple server exploits and crack complex passwords. Defend systems and networks: make your servers invisible, be confident of your security with penetration testing and repel unwelcome attackers. Increase your background knowledge of attacks on systems and networks and improve all-important practical skills required to secure any Linux server. The techniques presented apply to almost all Linux distributions including the many Debian and Red Hat derivatives and some other Unix-type systems. Further your career with this intriguing, deeply insightful, must-have technical book. Diverse, broadly-applicable and hands-on practical, Linux Server Security: Hack and Defend is an essential resource which will sit proudly on any techie's bookshelf.

Linux consistently turns up high in the list of popular Internet servers, whether it's for the Web, anonymous FTP, or general services like DNS and routing mail. But security is uppermost on the mind of anyone providing such a service. Any server experiences casual probe attempts dozens of time a day, and serious break-in attempts with some frequency as well. As the cost of broadband and other high-speed Internet connectivity has gone down, and its availability has increased, more Linux users are providing or considering providing Internet services such as HTTP, Anonymous FTP, etc., to the world at large. At the same time, some important, powerful, and popular Open Source tools have emerged and rapidly matured--some of which rival expensive commercial equivalents--making Linux a particularly appropriate platform for providing secure Internet services. Building Secure Servers with Linux will help you master the principles of reliable system and network security by combining practical advice with a firm knowledge of the technical tools needed to ensure security. The book focuses on the most common use of Linux--as a hub offering services to an organization or the larger Internet--and shows readers how to harden their hosts against attacks. Author Mick Bauer, a security consultant, network architect, and lead author of the popular Paranoid Penguin column in Linux Journal, carefully outlines the security risks, defines precautions that can minimize those risks, and offers recipes for robust security. The book does not cover firewalls, but covers the more common situation where an organization protects its hub using other systems as firewalls, often proprietary firewalls. The book includes: Precise directions for securing common services, including the Web, mail, DNS, and file transfer. Ancillary tasks, such as hardening Linux, using SSH and certificates for tunneling, and using iptables for firewalling. Basic installation of intrusion detection tools. Writing for Linux users with little security expertise, the author explains security concepts and techniques in clear language, beginning with the fundamentals. Building Secure Servers with Linux provides a unique balance of "big picture" principles that transcend specific software packages and version numbers, and very clear procedures on securing some of those software packages. An all-inclusive resource for Linux users who wish to harden their systems, the book covers general security as well as key services such as DNS, the Apache Web server, mail, file transfer, and secure shell. With this book in hand, you'll have everything you need to ensure robust security of your Linux system.

Implement Industrial-Strength Security on Any Linux Server In an age of mass surveillance, when advanced cyberwarfare weapons rapidly migrate into every hacker’s toolkit, you can’t rely on outdated security methods–especially if you’re responsible for Internet-facing services. In Linux® Hardening in Hostile Networks, Kyle Rankin helps you to implement modern safeguards that provide maximum impact with minimum effort and to strip away old techniques that are no longer worth your time. Rankin provides clear, concise guidance on modern workstation, server, and network hardening, and explains how to harden specific services, such as web servers, email, DNS, and databases. Along the way, he demystifies technologies once viewed as too complex or mysterious but now essential to mainstream Linux security. He also includes a full chapter on effective incident response that both DevOps and SecOps can use to write their own incident response plan. Each chapter begins with techniques any sysadmin can use quickly to protect against entry-level hackers and presents intermediate and advanced techniques to safeguard against sophisticated and knowledgeable attackers, perhaps even state actors. Throughout, you learn what each technique does, how it works, what it does and doesn’t protect against, and whether it would be useful in your environment. Apply core security techniques including 2FA and strong passwords Protect admin workstations via lock screens, disk encryption, BIOS passwords, and other methods Use the security-focused Tails distribution as a quick path to a hardened workstation Compartmentalize workstation tasks into VMs with varying levels of trust Harden servers with SSH, use apparmor and sudo to limit the damage attackers can do, and set up remote syslog servers to track their actions Establish secure VPNs with OpenVPN, and leverage SSH to tunnel traffic when VPNs can’t be used Configure a software load balancer to terminate SSL/TLS connections and initiate new ones downstream Set up standalone Tor services and hidden Tor services and relays Secure Apache and Nginx web servers, and take full advantage of HTTPS Perform advanced web server hardening with HTTPS forward secrecy and ModSecurity web application firewalls Strengthen email security with SMTP relay authentication, SMTPS, SPF records, DKIM, and DMARC Harden DNS servers, deter their use in DDoS attacks, and fully implement DNSSEC Systematically protect databases via network access control, TLS traffic encryption, and encrypted data storage Respond to a compromised server, collect evidence, and prevent future attacks Register your product at informit.com/register for convenient access to downloads, updates, and corrections as they become available.

A comprehensive guide to mastering the art of preventing your Linux system from getting compromised. Key Features Leverage this guide to confidently deliver a system that reduces the risk of being hacked Perform a number of advanced Linux security techniques such as network service detection, user authentication, controlling special permissions, encrypting file systems, and much more Master the art of securing a Linux environment with this end-to-end practical guide Book DescriptionThis book has extensive coverage of techniques that will help prevent attackers from breaching your system, by building a much more secure Linux environment. You will learn various security techniques such as SSH hardening, network service detection, setting up firewalls, encrypting file systems, protecting user accounts, authentication processes, and so on. Moving forward, you will also develop hands-on skills with advanced Linux permissions, access control, special modes, and more. Lastly, this book will also cover best practices and troubleshooting techniques to get your work done efficiently. By the end of this book, you will be confident in delivering a system that will be much harder to compromise.What you will learn Use various techniques to prevent intruders from accessing sensitive data Prevent intruders from planting malware, and detect whether malware has been planted Prevent insiders from accessing data that they aren’t authorized to access Do quick checks to see whether a computer is running network services that it doesn’t need to run Learn security techniques that are common to all Linux distros, and some that are distro-specific Who this book is for If you are a systems administrator or a network engineer interested in making your Linux environment more secure, then this book is for you. Security consultants wanting to enhance their Linux security skills will also benefit from this book. Prior knowledge of Linux is mandatory.

A comprehensive guide to securing your Linux system against cyberattacks and intruders Key Features Deliver a system that reduces the risk of being hacked Explore a variety of advanced Linux security techniques with the help of hands-on labs Master the art of securing a Linux environment with this end-to-end practical guide Book DescriptionFrom 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.What you will learn Create locked-down user accounts with strong passwords Configure firewalls with iptables, UFW, nftables, and firewalld Protect your data with different encryption technologies Harden the secure shell service to prevent security break-ins Use mandatory access control to protect against system exploits Harden kernel parameters and set up a kernel-level auditing system Apply OpenSCAP security profiles and set up intrusion detection Configure securely the GRUB 2 bootloader and BIOS/UEFI Who this book is for This 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.

Computer security is an ongoing process, a relentless contest between system administrators and intruders. A good administrator needs to stay one step ahead of any adversaries, which often involves a continuing process of education. If you're grounded in the basics of security, however, you won't necessarily want a complete treatise on the subject each time you pick up a book. Sometimes you want to get straight to the point. That's exactly what the new Linux Security Cookbook does. Rather than provide a total security solution for Linux computers, the authors present a series of easy-to-follow recipes--short, focused pieces of code that administrators can use to improve security and perform common tasks securely.The Linux Security Cookbook includes real solutions to a wide range of targeted problems, such as sending encrypted email within Emacs, restricting access to network services at particular times of day, firewalling a webserver, preventing IP spoofing, setting up key-based SSH authentication, and much more. With over 150 ready-to-use scripts and configuration files, this unique book helps administrators secure their systems without having to look up specific syntax. The book begins with recipes devised to establish a secure system, then moves on to secure day-to-day practices, and concludes with techniques to help your system stay secure.Some of the "recipes" you'll find in this book are: Controlling access to your system from firewalls down to individual services, using iptables, ipchains, xinetd, inetd, and more Monitoring your network with tcpdump, dsniff, netstat, and other tools Protecting network connections with Secure Shell (SSH) and stunnel Safeguarding email sessions with Secure Sockets Layer (SSL) Encrypting files and email messages with GnuPG Probing your own security with password crackers, nmap, and handy scripts This cookbook's proven techniques are derived from hard-won experience. Whether you're responsible for security on a home Linux system or for a large corporation, or somewhere in between, you'll find valuable, to-the-point, practical recipes for dealing with everyday security issues. This book is a system saver.

*Imparts good security doctrine, methodology, and strategies *Each application-focused chapter will be able to be used as a stand-alone HOW-TO for that particular application. *Offers users a selection of resources (websites, mailing lists, and books) to further their knowledge.