Practical Linux Security Cookbook

Description

Over the last few years, system security has gained a lot of momentum and software professionals are focusing heavily on it. Linux is often treated as a highly secure operating system. However, the reality is that Linux has its share of security flaws, and these security flaws allow attackers to get into your system and modify or even destroy your important data. But there’s no need to panic, since there are various mechanisms by which these flaws can be removed, and this book will help you learn about different types of Linux security to create a more secure Linux system. With a step-by-step recipe approach, the book starts by introducing you to various threats to Linux systems. Then, this book will walk you through customizing the Linux kernel and securing local files. Next, you will move on to managing user authentication both locally and remotely and mitigating network attacks. Later, you will learn about application security and kernel vulnerabilities. You will also learn about patching Bash vulnerability, packet filtering, handling incidents, and monitoring system logs. Finally, you will learn about auditing using system services and performing vulnerability scanning on Linux. By the end of this book, you will be able to secure your Linux systems and create a robust environment. What you will learn: Learn about vulnerabilities and exploits in relation to Linux systems. Configure and build a secure kernel and test it. Learn about file permissions and how to securely modify files. Authenticate users remotely and securely copy files on remote systems. Review different network security methods and tools. Perform vulnerability scanning on Linux machines using tools. Learn about malware scanning and read through logs. This book is intended for all those Linux users who already have knowledge of Linux file systems and administration. You should be familiar with basic Linux commands. Understanding information security and its risks to a Linux system is also helpful in understanding the recipes more easily. Cover......Page 0 Title Page......Page 2 Copyright and Credits......Page 3 Contributors......Page 4 Packt Upsell......Page 6 Table of Contents......Page 7 Preface......Page 17 Security policy......Page 23 Myth – as Linux is open source, it is considered to be insecure......Page 24 User management......Page 25 Configuration policy......Page 26 Security policy – server security......Page 27 Configuration policy......Page 28 Installation......Page 29 Network and services......Page 30 Checking the integrity of installation medium by using checksum......Page 31 See also......Page 32 Getting ready......Page 33 How to do it.........Page 34 There's more.........Page 38 How to do it…......Page 39 Getting ready......Page 42 How to do it.........Page 43 How it works.........Page 46 How to do it.........Page 47 How to do it.........Page 51 Amanda (Advanced Maryland Automatic Network Disk Archiver)......Page 52 How it works.........Page 53 Chapter 2: Configuring a Secure and Optimized Kernel......Page 54 How to do it.........Page 55 How it works.........Page 56 How to do it.........Page 57 Configuring and building kernel......Page 58 How to do it.........Page 59 How to do it.........Page 65 How it works.........Page 67 Getting ready......Page 68 How to do it.........Page 70 There's more.........Page 74 How to do it.........Page 75 Causes of kernel errors......Page 77 Checking kernel parameters using Lynis......Page 79 How to do it.........Page 80 Getting ready......Page 84 How to do it…......Page 85 How to do it.........Page 87 There's more.........Page 90 How to do it.........Page 91 There's more.........Page 93 Getting ready......Page 94 How to do it.........Page 95 There's more.........Page 97 How it works.........Page 98 Getting ready......Page 103 How to do it.........Page 105 Getting ready......Page 106 How to do it.........Page 107 Installing and configuring a basic LDAP server on Ubuntu......Page 108 How to do it.........Page 109 How it works.........Page 116 User authentication and logging......Page 117 How to do it.........Page 118 Getting ready......Page 121 How to do it.........Page 122 Getting ready......Page 125 How to do it.........Page 126 Getting ready......Page 128 How to do it.........Page 131 How it works.........Page 132 How to do it.........Page 133 There's more.........Page 138 How to do it.........Page 139 Getting ready......Page 142 How to do it.........Page 144 How it works.........Page 147 Getting ready......Page 148 How to do it.........Page 149 How to do it.........Page 153 There's more.........Page 156 Getting ready......Page 157 How to do it.........Page 158 Copying files remotely......Page 160 How to do it.........Page 161 How it works.........Page 165 Getting started......Page 166 How to do it.........Page 167 How it works.........Page 175 How to do it.........Page 176 Getting ready......Page 182 How to do it.........Page 183 How to do it.........Page 187 How it works.........Page 191 How to do it.........Page 192 Getting ready......Page 197 How to do it.........Page 198 How to do it.........Page 201 How it works.........Page 205 How to do it.........Page 206 Getting ready......Page 211 How to do it.........Page 212 Getting ready......Page 216 How to do it.........Page 217 How it works.........Page 222 Linux sXID......Page 223 How to do it.........Page 224 Getting ready......Page 226 How to do it.........Page 227 Using Squid proxy......Page 231 How to do it.........Page 232 How it works.........Page 236 Getting ready......Page 237 How to do it.........Page 238 How it works.........Page 242 There's more.........Page 243 Getting ready......Page 244 How to do it.........Page 245 Getting ready......Page 252 How to do it.........Page 253 How it works.........Page 256 Getting ready......Page 257 How to do it.........Page 258 Getting ready......Page 266 How to do it.........Page 267 Rsync and Grsync – backup tool......Page 271 Getting ready......Page 272 How to do it.........Page 273 How it works.........Page 278 Kali Linux......Page 279 Getting ready......Page 287 How to do it.........Page 288 How it works.........Page 294 Digital Evidence and Forensic Toolkit  (DEFT)......Page 295 How to do it.........Page 297 How to do it.........Page 302 How it works.........Page 310 Getting ready......Page 311 How to do it.........Page 312 Getting ready......Page 315 How to do it.........Page 316 How it works.........Page 326 Getting ready......Page 327 How to do it.........Page 328 Security issues – Shellshock......Page 331 How to do it.........Page 332 Getting ready......Page 338 How to do it.........Page 339 Applying patches in Linux......Page 345 How to do it.........Page 346 How to do it.........Page 349 How it works.........Page 350 Viewing and managing log files using Logcheck......Page 351 How to do it.........Page 352 Monitoring the network using Nmap......Page 355 How to do it.........Page 356 How it works.........Page 360 How to do it.........Page 361 How it works.........Page 364 Getting ready......Page 365 How to do it.........Page 366 How it works.........Page 368 How to do it.........Page 369 How it works......Page 372 How to do it.........Page 373 How it works.........Page 376 How to do it.........Page 377 How it works.........Page 379 How to do it.........Page 380 Real time IP LAN monitoring using IPTraf......Page 383 How to do it.........Page 384 Getting ready......Page 389 How to do it.........Page 390 Network monitoring using OpenNMS......Page 395 Getting ready......Page 396 How to do it.........Page 398 How it works......Page 404 Getting ready......Page 405 How to do it.........Page 406 Getting ready......Page 408 How to do it.........Page 409 Secure remote login – SSH......Page 411 How to do it.........Page 412 File transfer security – FTP......Page 413 How to do it.........Page 415 How it works.........Page 422 Getting ready......Page 423 How to do it.........Page 424 Scanning with ClamAV......Page 426 How to do it.........Page 427 How to do it.........Page 431 How it works.........Page 435 How to do it.........Page 436 How to do it.........Page 438 How to do it.........Page 444 How it works.........Page 447 Network security monitoring using Security Onion......Page 448 How to do it.........Page 449 How to do it.........Page 453 Getting ready......Page 460 How to do it.........Page 461 How it works.........Page 462 How to do it.........Page 463 How it works.........Page 467 Other Books You May Enjoy......Page 468 Index......Page 471