During a project I had a situation where I needed to use a double proxy in order to intercept traffic with Burpsuite. So I’m gonna explain how to configure burp to act as a double proxy.
First thing first I will assume you have worked with burp before. I just skip to the point.
Once in burp proxy you’ll need to configure a second proxy to act as a listener, I suggest to bind a port that’s not being used and also to listen on every interface (the asterix), just like the image below.
Second go to project options and mark Upstream Proxy Servers checkbox. Once that is done it will ask you to input the other proxy configuration data (IP, Port, Credentials and some other data).
Once that’s done everything that passes burp will be redirected to the outgoing proxy and should be looking like this:
Have fun and keep hacking.