Sec Auditing: Burp Suite

Introduction

Burp Suite is a comprehensive platform for web application security testing. It is developed by PortSwigger Web Security and is widely used by security professionals for conducting security assessments of web applications. Burp Suite offers a range of tools with powerful features, making it a favorite among penetration testers for its versatility and effectiveness in identifying vulnerabilities.

Key Components of Burp Suite

Burp Suite includes several integrated tools that work together seamlessly to support the entire testing process, from initial mapping to analysis and exploitation of vulnerabilities. Some of its main components include:

• Proxy: The core tool of Burp Suite, it acts as an intermediary between the user's browser and the web servers. This allows for the interception, review, and modification of requests and responses, making it invaluable for testing how the application behaves under malicious inputs.

• Scanner: An automated vulnerability scanner that can identify numerous types of vulnerabilities in web applications. It's known for its accuracy and the detailed information it provides, which includes the potential impact and pointers to where the vulnerabilities are located.

• Intruder: This tool is used for automating customized attacks against web applications. It allows for the setting of payloads, attack types, and other configurations to test for vulnerabilities like SQL injection, cross-site scripting (XSS), and more.

• Repeater: It allows for the manual modification and resending of individual HTTP requests. This is useful for testing the server’s response to modified or anomalous input.

• Sequencer: Used for testing the randomness of session tokens and other data items that are intended to be unpredictable.

• Decoder: A tool for transforming encoded data into its canonical form, or vice versa, useful in testing applications that use various data encoding schemes.

• Comparer: It allows for the side-by-side comparison of two data items, which is particularly useful in situations like comparing the responses to two different requests.

• Extender: This allows users to load Burp Suite extensions, many of which are developed by the Burp community and extend the functionality of Burp Suite in various ways.

Features

• Intercepting Proxy: Allows for viewing and modifying all requests and responses between the browser and the web server.

• Detailed Analysis and Reporting: Burp Suite provides detailed analysis and reporting of vulnerabilities, helping in understanding their severity and impact.

• Customizability: It offers a high degree of customizability to cater to the specific needs of different testing scenarios.

• Automation and Manual Testing: Burp Suite supports both automated and manual testing methods, giving testers flexibility and control over their testing procedures.

Use Cases

• Security Testing of Web Applications: Identify vulnerabilities like SQL injection, XSS, CSRF, and more.

• Session Management Testing: Analyze session tokens and cookies for weaknesses.

• Data Validation Testing: Test how the application handles unexpected or malicious input.

Why Burp Suite is Popular Among Security Professionals

• Comprehensive Testing Tool: It covers a wide range of testing needs in a single platform.

• User-Friendly Interface: Despite its extensive capabilities, Burp Suite maintains a user-friendly interface.

• Community and Extensibility: A strong community and the ability to extend functionality through plugins and extensions.

• Regular Updates: Burp Suite is regularly updated to address new security challenges and incorporate feedback from its user base.

Basic Guide

Burp Suite is a popular tool for web application security testing and is included in Kali Linux, a Linux distribution designed for digital forensics and penetration testing. Here's a basic guide on how to use Burp Suite on Kali Linux:

Installation

Burp Suite is pre-installed on Kali Linux, so you typically don't need to install it separately. However, if it's not installed, you can install it by:

1. Updating the Package List: Open a terminal and run 'sudo apt-get update' to update your package list.

2. Installing Burp Suite: Run 'sudo apt-get install burpsuite'.

Running Burp Suite

1. Launch Burp Suite: You can start Burp Suite by searching for it in your applications menu or by typing 'burpsuite' in the terminal.

2. Initial Configuration: When you first run Burp Suite, you'll be presented with a configuration screen. For most users, the default settings are sufficient.

 Basic Usage

1. Proxy Setup: To intercept web traffic, configure your browser to use Burp as its proxy. The default settings are usually '127.0.0.1' for the IP and '8080' for the port.

2. Intercepting Requests: Go to the “Proxy” tab in Burp Suite and ensure “Intercept is on.” Then, when you navigate your browser, the requests and responses will be captured by Burp.

3. Analyzing and Modifying Requests: You can view, modify, and forward HTTP requests and responses. This is useful for testing how applications respond to modified inputs.

4. Using Other Tools: Burp Suite includes various tools like Repeater, Intruder, Scanner, etc., for different testing purposes. Explore these tools to perform more advanced testing like automated scans, customized attacks, etc.

Saving and Restoring Work

• Save Your Work: You can save your current state by going to the “Project” menu and selecting “Save state.”

• Restoring: To restore a saved state, start Burp Suite and choose to open an existing project, then select your saved project file.

 Updating Burp Suite

• Regularly update Burp Suite to get the latest features and security updates. You can update it through Kali's package manager by running 'sudo apt-get update' and 'sudo apt-get upgrade'.

Notes: 

• Permissions: Some features of Burp Suite might require root permissions, so use 'sudo' if necessary.

• Learning Resources: Burp Suite has a bit of a learning curve, so consider checking out their official documentation, tutorials, and community forums for in-depth learning.

Remember, use Burp Suite ethically and legally. It's a powerful tool intended for security testing and research, not for unauthorized hacking.

Conclusion

Burp Suite stands as a cornerstone tool in the field of web application security testing. Its comprehensive set of features, combined with its flexibility and extensibility, make it an essential tool for cybersecurity professionals focused on identifying and mitigating web application vulnerabilities. Whether for routine security audits or complex penetration testing scenarios, Burp Suite provides the necessary toolkit to thoroughly evaluate the security posture of web applications.

NEXT: Forensics Tools: Autopsy and Sleuth Kit