Book Image

Antivirus Bypass Techniques

By : Nir Yehoshua, Uriel Kosayev
Book Image

Antivirus Bypass Techniques

By: Nir Yehoshua, Uriel Kosayev

Overview of this book

Antivirus software is built to detect, prevent, and remove malware from systems, but this does not guarantee the security of your antivirus solution as certain changes can trick the antivirus and pose a risk for users. This book will help you to gain a basic understanding of antivirus software and take you through a series of antivirus bypass techniques that will enable you to bypass antivirus solutions. The book starts by introducing you to the cybersecurity landscape, focusing on cyber threats, malware, and more. You will learn how to collect leads to research antivirus and explore the two common bypass approaches used by the authors. Once you’ve covered the essentials of antivirus research and bypassing, you'll get hands-on with bypassing antivirus software using obfuscation, encryption, packing, PowerShell, and more. Toward the end, the book covers security improvement recommendations, useful for both antivirus vendors as well as for developers to help strengthen the security and malware detection capabilities of antivirus software. By the end of this security book, you'll have a better understanding of antivirus software and be able to confidently bypass antivirus software.
Table of Contents (13 chapters)
1
Section 1: Know the Antivirus – the Basics Behind Your Security Solution
5
Section 2: Bypass the Antivirus – Practical Techniques to Evade Antivirus Software
9
Section 3: Using Bypass Techniques in the Real World

Antivirus bypass using a DLL

A DLL is a library file containing number of functions (sometimes hundreds or more) that are, as the name suggests, dynamically loaded and used by Windows PE files.

DLL files either include or actually export Windows and Native API functions that are used or imported by PE executables. Those DLLs are used by various programs such as antivirus software programs, easing development by letting coders call a wide range of prewritten functions.

To understand better what a DLL file is, as well as any other PE-based file types, it is important to understand the PE file format.

PE files

PE files play an important role in the Windows operating system. This file format is used by executable binary files with the .exe extension as well as by DLLs with the .dll extension, but those are not only the file types using this versatile file format. Here are a few others:

  • CPL: Base file for control panel configurations, which plays a basic and important...