Introduction to Burp Suite

Burp Suite is a comprehensive tool for web security testing, widely used by professionals in the field. It includes various modules such as a vulnerability scanner, traffic analyzer, and more. One of the powerful features of Burp Suite is its ability to be extended with custom plugins, which can significantly enhance its functionality. In this article, we will explore how to develop extensions for Burp Suite using Python.

Setting Up the Environment

Before you start developing extensions, you need to set up your environment. Here are the steps to follow:

  1. Install Burp Suite: Download and install Burp Suite from the official website. You can use either the free or professional version, but the professional version offers more advanced features.

  2. Configure Python Environment: To develop extensions, you need to configure the Python environment within Burp Suite. Here’s how you can do it:

    • Open Burp Suite and navigate to Extender > Options > Python Environment.
    • Select the Python interpreter you want to use and specify the path to your Python installation.

  3. Install Required Libraries: You may need to install additional libraries depending on the functionality of your extension. You can do this using pip:

    pip install <library-name>

Creating a Basic Extension

To create a basic extension, you need to write a Python script that interacts with Burp Suite’s API. Here’s a step-by-step guide:

  1. Create a New Python File: Create a new Python file, for example, my_extension.py.

  2. Import Burp Suite’s API: Import the necessary modules from Burp Suite’s API:

    from burp import IBurpExtender
from burp import IScannerCheck
from burp import IIntruderPayloadProcessor

  3. Define the Extension Class: Define a class that implements the IBurpExtender interface. This class will contain the main logic of your extension:

    class BurpExtender(IBurpExtender):
    def __init__(self):
        self._callbacks = None

    def registerExtenderCallbacks(self, callbacks):
        self._callbacks = callbacks
        self._callbacks.setExtensionName("My Extension")
        # Register other callbacks here if needed
        return

  4. Implement Additional Interfaces: Depending on what you want your extension to do, you may need to implement additional interfaces such as IScannerCheck for vulnerability scanning or IIntruderPayloadProcessor for payload processing:

    class MyScannerCheck(IScannerCheck):
    def doPassiveScan(self, baseRequestResponse):
        # Implement passive scan logic here
        return []

    def doActiveScan(self, baseRequestResponse, insertionPoint):
        # Implement active scan logic here
        return []

  5. Load the Extension: To load your extension into Burp Suite, go to Extender > Extensions > Add and select your Python file.

Example: CORS Misconfiguration Scanner

Here’s an example of how you can create an extension to scan for CORS misconfiguration using Python:

  1. Import Necessary Modules:

    from burp import IBurpExtender
from burp import IScannerCheck
from burp import IHttpService
from burp import IHttpRequestResponse
from burp import IHttpRequestResponseWithMarkers

  2. Define the Extension Class:

    class BurpExtender(IBurpExtender, IScannerCheck):
    def __init__(self):
        self._callbacks = None

    def registerExtenderCallbacks(self, callbacks):
        self._callbacks = callbacks
        self._callbacks.setExtensionName("CORS Misconfiguration Scanner")
        self._callbacks.registerScannerCheck(self)
        return

    def doPassiveScan(self, baseRequestResponse):
        # Get the HTTP response
        response = baseRequestResponse.getResponse()
        if response is None:
            return []

        # Check for CORS headers
        headers = self._callbacks.getHelpers().analyzeResponse(response).getHeaders()
        cors_headers = [header for header in headers if header.startswith("Access-Control-")]

        if not cors_headers:
            return []

        # Check for misconfiguration
        if "Access-Control-Allow-Origin: *" in [header for header in headers]:
            # Report the issue
            issue = self._callbacks.createIssue(
                baseRequestResponse.getHttpService(),
                baseRequestResponse.getUrl(),
                [baseRequestResponse],
                "CORS Misconfiguration",
                "The server allows CORS requests from any origin.",
                "Medium"
            )
            return [issue]

        return []

Advanced Features and Customization

Burp Suite provides a wide range of features that you can leverage in your extensions, including:

  • Traffic Analysis: You can analyze HTTP traffic using the IHttpRequestResponse and IHttpService interfaces.
  • Payload Processing: You can process payloads using the IIntruderPayloadProcessor interface.
  • Custom UI: You can create custom UI components using the ISwingCustomizer interface.

Conclusion

Developing extensions for Burp Suite using Python is a powerful way to enhance its functionality and automate various tasks related to web security testing. By following the steps outlined in this article, you can create custom extensions that fit your specific needs. Remember to explore the official Burp Suite documentation and API for more detailed information on available interfaces and methods.

Additional Resources

  • Burp Suite Documentation: The official Burp Suite documentation provides detailed information on its API and how to develop extensions.
  • Habr Articles: There are several articles on Habr that discuss various aspects of web security testing and extension development for Burp Suite.
  • Community Forums: The Burp Suite community forums are a great resource for asking questions and getting help from other users and developers.

By leveraging these resources and following the guidelines provided in this article, you can become proficient in developing extensions for Burp Suite and take your web security testing to the next level.