Book Image

Hands-On Network Forensics

By : Nipun Jaswal
2 (2)
Book Image

Hands-On Network Forensics

2 (2)
By: Nipun Jaswal

Overview of this book

Network forensics is a subset of digital forensics that deals with network attacks and their investigation. In the era of network attacks and malware threat, it’s now more important than ever to have skills to investigate network attacks and vulnerabilities. Hands-On Network Forensics starts with the core concepts within network forensics, including coding, networking, forensics tools, and methodologies for forensic investigations. You’ll then explore the tools used for network forensics, followed by understanding how to apply those tools to a PCAP file and write the accompanying report. In addition to this, you will understand how statistical flow analysis, network enumeration, tunneling and encryption, and malware detection can be used to investigate your network. Towards the end of this book, you will discover how network correlation works and how to bring all the information from different types of network devices together. By the end of this book, you will have gained hands-on experience of performing forensics analysis tasks.
Table of Contents (16 chapters)
Free Chapter
1
Section 1: Obtaining the Evidence
4
Section 2: The Key Concepts
8
Section 3: Conducting Network Forensics

Decrypting TLS using browsers

One of the hidden features of the popular Chrome browser is the support of logging the symmetric session key used while encrypting the traffic with TLS to a file of our choice. Let's see what happens when we try to capture a TLS-encrypted packet:

We can see that the network traffic is encrypted using TLS and that the data in the bottom pane is not making much sense to us. Fortunately, browsers such as Chrome support storing the TLS key, which can help us decrypt the data that otherwise is not making sense. To set up logging, we need to export a user environment variable by browsing the Control Panel and opening system.

Next, we need to choose Advanced system settings. In the next step, we will choose the Environment Variables... option. In the User variable section, we will add the SSLKEYLOGFILE variable by clicking New and then set...