Book Image

Mastering Python Forensics

Book Image

Mastering Python Forensics

Overview of this book

Digital forensic analysis is the process of examining and extracting data digitally and examining it. Python has the combination of power, expressiveness, and ease of use that makes it an essential complementary tool to the traditional, off-the-shelf digital forensic tools. This book will teach you how to perform forensic analysis and investigations by exploring the capabilities of various Python libraries. The book starts by explaining the building blocks of the Python programming language, especially ctypes in-depth, along with how to automate typical tasks in file system analysis, common correlation tasks to discover anomalies, as well as templates for investigations. Next, we’ll show you cryptographic algorithms that can be used during forensic investigations to check for known files or to compare suspicious files with online services such as VirusTotal or Mobile-Sandbox. Moving on, you’ll learn how to sniff on the network, generate and analyze network flows, and perform log correlation with the help of Python scripts and tools. You’ll get to know about the concepts of virtualization and how virtualization influences IT forensics, and you’ll discover how to perform forensic analysis of a jailbroken/rooted mobile device that is based on iOS or Android. Finally, the book teaches you how to analyze volatile memory and search for known malware samples based on YARA rules.
Table of Contents (14 chapters)

Algorithms


In this section, we describe the main differences between MD5, SHA256, and SSDEEP—the most common algorithms used in the forensic investigations. We will explain the use cases as well as the limitations and threats behind these three algorithms. This should help you understand why using SHA256 is better than using MD5 and in which cases SSDEEP can help you in the investigation.

Before we dive into the different hash functions, we will give a short summary of what a cryptographic hash function is.

A hash function is a function that maps an arbitrarily large amount of data to a value of a fixed length. The hash function ensures that the same input always results in the same output, called the hash sum. Consequently, a hash sum is a characteristic of a specific piece of data.

A cryptographic hash function is a hash function that is considered practically impossible to invert. This means that it is not possible to create the input data while having a pre-defined hash sum value by any...