Book Image

Malware Analysis Techniques

By : Dylan Barker
Book Image

Malware Analysis Techniques

By: Dylan Barker

Overview of this book

Malicious software poses a threat to every enterprise globally. Its growth is costing businesses millions of dollars due to currency theft as a result of ransomware and lost productivity. With this book, you'll learn how to quickly triage, identify, attribute, and remediate threats using proven analysis techniques. Malware Analysis Techniques begins with an overview of the nature of malware, the current threat landscape, and its impact on businesses. Once you've covered the basics of malware, you'll move on to discover more about the technical nature of malicious software, including static characteristics and dynamic attack methods within the MITRE ATT&CK framework. You'll also find out how to perform practical malware analysis by applying all that you've learned to attribute the malware to a specific threat and weaponize the adversary's indicators of compromise (IOCs) and methodology against them to prevent them from attacking. Finally, you'll get to grips with common tooling utilized by professional malware analysts and understand the basics of reverse engineering with the NSA's Ghidra platform. By the end of this malware analysis book, you’ll be able to perform in-depth static and dynamic analysis and automate key tasks for improved defense against attacks.
Table of Contents (17 chapters)
1
Section 1: Basic Techniques
6
Section 2: Debugging and Anti-Analysis – Going Deep
11
Section 3: Reporting and Weaponizing Your Findings
14
Section 4: Challenge Solutions

Deobfuscating malicious PowerShell scripts

Perhaps one of the most common scripting languages in use for both malicious and legitimate administration purposes is the built-in Windows scripting engine based on .NET—PowerShell.

PowerShell has been embraced readily by threat actors, red teamers, and systems administrators alike to accomplish their ends due to its power.

As a result of this power, it's also incredibly easy to obfuscate PowerShell scripts in many different ways. We'll take a look at a few examples exclusive to PowerShell, and a real-world example utilized by Emotet!

First, we'll take a look at a few examples that are utilized by PowerShell that are generally unique to PowerShell malware samples.

Compression

The first method (which is one of the most commonly utilized obfuscation methods) is compression, as shown in the following code snippet:

.($pshOme[21]+$PsHomE[30]+'X') (NEw-obJECt  iO.STREAmREAdER ( ( NEw...