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

Understanding protection rings

Before we explain vulnerabilities that can be exploited because of permission problems, it is important to understand the concept of protection rings in operating systems.

The term protection ring refers to a hierarchical mechanism implemented on CPUs and utilized by operating systems such as Windows to protect the system by providing fault tolerance and, of course, to better protect from malicious activity and behavior. Each ring in this mechanism has a unique role in the overall functioning of the operating system, as seen in the following illustration:

Figure 3.3 – Protection ring layers

The lower the number of the ring, the closer it is to the hardware and, therefore, the higher its privilege level. As you can see in the illustration, Ring 0 is the operating system kernel, which provides "back-to-back" access to the hardware from the higher rings and vice versa. Antivirus software tends to deploy its inspection...