Introduction to Burp Suite

Burp Suite is a leading tool for web security testing. It offers a range of features that allow security professionals to analyze, inspect, and modify web traffic. One of its powerful capabilities is the ability to manipulate HTTP headers, which can be invaluable for identifying vulnerabilities related to header values.

Importance of HTTP Headers

HTTP headers play a crucial role in web communication, providing metadata about the request or response. They can influence various aspects of the transaction, from content type to caching behavior. Manipulating these headers can expose potential security flaws in an application.

Example of HTTP Header Manipulation with Burp Suite

Let's take a look at a typical HTTP request header and see how it can be manipulated using Burp Suite:

Regular HTTP Header:

         GET /index.html HTTP/1.1
         Host: www.example.com
         User-Agent: Mozilla/5.0
         Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
         Accept-Language: en-US,en;q=0.5
         Accept-Encoding: gzip, deflate
         Connection: keep-alive
         

Manipulated HTTP Header:

         GET /index.html HTTP/1.1
         Host: attacker.com
         User-Agent: EvilBot/1.0
         Accept: */*
         Accept-Language: es-ES,es;q=0.9
         Accept-Encoding: gzip, deflate
         Connection: close
         X-Attack-Header: exploit_payload
         

In the manipulated header, we've changed the "Host" to a different domain, altered the "User-Agent" to represent a malicious bot, changed the "Accept" and "Accept-Language" headers, and added a custom "X-Attack-Header". This is just a hypothetical example to illustrate the potential changes an attacker might make. Always ensure you're conducting tests ethically and with proper authorization.

Setting Up Burp Suite

Before diving into HTTP header manipulation, ensure that Burp Suite is set up correctly.

Refer to this tutorial to setup & configure Burp Suite.

HTTP Header Manipulation with Burp Suite

With Burp Suite, you can intercept and modify HTTP requests and responses. Here's how to manipulate headers:

1. Under the "Proxy" tab, ensure "Intercept is on" is enabled.
2. Visit a website in your browser. The request will be intercepted by Burp Suite.
3. In the intercepted request, you can modify any header value or add new headers.
4. After making your changes, forward the request to see the server's response.

Host Header Attacks

One of the common header manipulation attacks is the Host Header Attack. By manipulating the Host header, attackers can poison web caches, exploit password reset features, or bypass security controls.

1. Intercept a request using Burp Suite.
2. Modify the "Host" header value to a different domain or an internal IP address.
3. Forward the request and observe the server's response to identify potential vulnerabilities.

For a detailed understanding of Host Header Attacks, refer to the official documentation by PortSwigger.

Conclusion

Burp Suite is an indispensable tool for web security testing. Its ability to manipulate HTTP headers provides a gateway to uncover potential vulnerabilities in web applications. As always, ensure you have the necessary permissions before testing and adhere to ethical guidelines.