Monday, 9 September 2013

BurpCSJ extension release

As part of my research and talk titled "Augmented Reality in your web proxy" presented during the HackPra AllStars program / OWASP AppSec EU 2013  security conference in Hamburg, I decided to release a new Burp Pro extension which integrates Crawljax, Selenium and JUnit.

I decided to take this approach to increase application spidering coverage (especially for Ajax web apps), speed up complex test-cases and take advantage of the Burp Extender API.

  • BurpCSJ extension JAR - download (all dependencies included)
  • BurpCSJ source code - github
  • "Augmented Reality in your web proxy" - presentation (slideshare)
Getting started
  1. Download BurpCSJ;
  2. Load BurpCSJ extension jar via the Extender tab;
  3. Choose the URL item from any Burp tab (e.g. target, proxy history, repeater); 
  4. Right click on the URL item;
  5. Choose menu item "Send URL to Crawljax";
  6. Crawljax will automatically start crawling the URL that you choose.



BurpCSJ extension in action:

BurpCSJ Tutorial - Using Crawljax

This is a simple tutorial to get you started with BurpCSJ and Crawljax.

Installation is easy - just download the BurpCSJ and import it in Burp via the extender tab, as shown below:

Extender -> Add -> Choose File

Once the extension is loaded, two new tabs will appear on the right side:

Start crawling

To start crawling, grab an URL item from any Burp tab (e.g. proxy history), right-click on the item and choose "Send to URL to Crawljax", as shown below:

After this, Crawljax session will start based on settings configured via the Crawljax tab.
It is always recommended to choose a web root URL item for Crawljax e.g. instead of a specific page or folder. This is typically the URL that you have configured under Target/Scope in Burp.

Crawling with a different browser

Under the Crawljax tab, it possible to configure the path to the browser drivers, proxy settings and other options for Crawljax.

If you need to use a different browser with Crawljax, then you would need to add the relevant drivers or executables:
In this example, let's use the Chrome driver:

Once chrome is selected, then you can start Crawljax with Chrome as described in the previous step.

Crawling application with login/authentication

If you are testing a web application with a login/authentication then it is recommended to use Burp cookie jar. This option allows BurpCSJ to pass cookies to Crawljax when crawling a site. If you already have session tokens in the cookie jar, then BurpCSJ will use those.

Exclusion list

The exclusion list allows to filter out unwanted pages, such as logout or signoff. More entries would be needed for complex applications, such as admnistrative interfaces where crawling might actually change or modify the application state.

Setting crawling for HTML elements

The last part allows more granular control on the HTML elements which would be considered by Crawljax. By enabling more HTML elements, it is possible to apply Crawljax logic against more elements. As a consequence, Crawljax session would probably take longer to complete.

Generating a report of crawling session

The CrawlOverview plugin can be invoked and a folder output needs to be set. At the end of the Crawljax session, the report will be generated under that folder.

An example of CrawOverview output can be seen here: