capt8bit · HackerTrans

This is common misinformation. Even in this case, OpenBSD did not break the embargo. After protesting, they received the permission of the researcher to publish:

  Note that I wrote and included a suggested diff for OpenBSD already, and that
  at the time the tentative disclosure deadline was around the end of August. As
  a compromise, I allowed them to silently patch the vulnerability.

(https://www.krackattacks.com/#openbsd)

capt8bit

10 lat temudiscuss

> (I am, for what it's worth, extremely familiar with Burp, but only casually acquainted with mitmproxy).

You may be disappointed, since I am the opposite. I use burp in rare cases now, since I've been using mitmproxy for so long.

>That's interesting to me. Can you describe your Burp workflow, and how you accomplish the same things in mitmproxy?

You may also be disappointed on how my methodology might differ. I work for a shop that performs grey-box (authenticated) web application tests that focus on manual comprehensive coverage. So my work flow goes something like this:

  - Manually walk the entire authenticated application, or designated portion. Populating all areas and using all application functionality.
  - Analyze mitmproxy logs to identify all application entry points, and other OWASP areas of interest. (mitmproxy's "Limit" feature makes this fast and easy)
  - Manually Test every endpoint, or other item, by duplicating the request, editing, and resending.

This is pretty basic, so I'm sure you see how this could be done with burp's repeater and intruder, which were the main areas I used.

In mitmproxy you can easily duplicate a flow, edit it, and resend it. Then, based on the response, resend it again. That's what I do for API testing, for web application testing it is usually closer to:

  - Stage requests in Hackbar on Firefox and send the request, which goes through mitmproxy.
  - Use Mitmproxy for fine-tuning anything, watching the details, and scripting the tedious.

> One of the things we're doing this year for our clients is selling them on the idea of doing basic security integration testing as part of their normal dev process, which might involve these companies buying copies of Burp for their team. But I could probably be convinced that mitmproxy would work just as well.

My basic common work flow is probably not very helpful in this case, but I think mitmproxy could still be very helpful to you. You probably know that mitmproxy can replay a series of requests, and has a great scripting API. I think these two features could be used together to meet a lot of your needs. Let me tell you about some of my experiences:

In some cases a customer just can't get their fix quite right, so I will need to repeatedly perform a series of tedious steps to retest an issue. So, I automate the process by using mitmproxy to save a file of the steps involved in testing the vulnerability. This may be something like:

  Log in -> Create widget -> edit widget -> destroy widget -> submit note

Then, I can pass this to mitmdump to be replayed, with sticky-cookies enabled, and I just watch the output to make sure the output is correct.

As far as scripting goes, you may be interested in cases where I wanted to quickly test every input parameter for input validation of a list of characters. The script I wrote would be run on every request I made to the site I was testing, if it was a post request it would do the following:

  - Duplicate the request for every POST parameter in the request
  - Inject the list of characters in to the post parameter
  - Run/Replay the new request

Hopefully you can make sense of my examples. I think by replaying request, or writing simple testing scripts, you could automate a lot of the basic security integration testing.

The beautiful thing about mitmproxy is that it has a simple, powerful, scriptable, core. By using the powerful building-blocks it's provided I can make it do whatever I want it to do. But, it may require a little python scripting.

Let me know if want additional attempts at clarification.

edited for formatting

capt8bit

10 lat temudiscuss

I have used mitmproxy for performing web application pentest for years.

If you want something to create/intercept/edit/tamper/replay requests, this is your tool. If you want to script any of those things, this is still your tool.

However, burp comes with a lot of bells and whistles that don't make a lot of sense to build in to mitmproxy, but you can script yourself. For example, there is no intruder, spider, or scanner tool. But, they have an easy to use interface to write scripts that will be run on every request you make, or individual requests.

Or, you can just pass all mitmproxy traffic out to burp and get the best of both worlds.

capt8bit

10 lat temudiscuss

Many thanks to you, cortesi, and the rest of the team.

I hope this doesn't mean that the command-line interface is going to become a second-class interface? The CLI is what originally attracted me to mitmproxy. Having CLI keyboard shortcuts helped me immediately speed up my workflow faster than I was ever able to customize ZAP or Burp.

I love mitmproxy and use it for all my web application pentests. The flexibility is amazing, and allows me to quickly adapt, or write a rewrite rule or plugin, in any situation. Regex rules for limits and intercepts are amazing too.

Keep up the good work.

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