Re: IIS 5.0 with Integrated Window Authentication

From: cc_mofo@hushmail.com
Date: Tue Nov 12 2002 - 18:34:02 EST


One last followup to this.

Using APS, I was able to detect and exploit a web app authentication design flaw (don't trust those cookies, kids, especially ones named something like "userid") in the target app.

I discovered some interesting behavior with IIS and IWA/NTLM. IIS *sometimes* closes the connection after telling the browser to use NTLM. It appears that several of the web proxy tools out there assume that the connection will stay open. Whisker has NTLM support, but I was unable to get it to work.

I worked with Dave Aitel to get SPIKE Proxy to support this behavior as well. SPIKE Proxy now works with NTLM at my site. Using SPIKE's UI I can now demo this exploit to developers and management more effectively (whereas with APS I had to manually insert Python code).

On Thu, 07 Nov 2002 13:25:56 -0800 cc_mofo@hushmail.com wrote:
>Thanks to everyone for the responses. I've gotten APS up and running
>and it works as advertised, i.e. perfectly. It does of course require
>that any tool that I use have proxy support (whisker just got proxy
>support with 2.0, and even then I don't have it working against
>APS yet).
>
>I understand WebInspect might work, so I will try it once their
>license squad finishes working me over.
>
>I'll take another look at SPIKE proxy for this at some point---last
>time I wound up in the weeds (code weeds, that is) trying to track
>down why/where it didn't work.
>
>On Thu, 07 Nov 2002 11:35:23 -0800 Dave Aitel <dave@immunitysec.com>
>wrote:
>>Hmm. My basterdized SPIKE Proxy NTLM auth does, in fact, work through
>>the proxy though.
>>
>>Client->SPIKE Proxy->Server
>>
>>Where Client is sending Proxy-Authorization, and SPIKE Proxy is
>>translating that into Authorization: and sending it to the server
>>and so
>>on. I get access on IIS 5.0, at least.
>>
>>
>>-dave
>>
>>On Wed, 6 Nov 2002 23:27:54 +0100
>>Sebastian Flothow <sebastian@flothow.de> wrote:
>>
>>> > The goofy three-message exchange that sets up the NTLM security
>>> > doesn't seem to make it through the proxy,
>>>
>>> AFAIK, NTLM _can_ _not_ work through proxies, by design. It seems
>>it
>>> includes the client's IP address, which then doesn't match that
>>of the
>>>
>>> proxy (which is the client from the server's point of view),
>or
>>
>>> something similar.
>>>
>>>
>>> Sebastian
>>>
>>> --
>>> Sebastian Flothow
>>> sebastian@flothow.de
>>> #include <stddisclaimer.h>
>>>
>>>
>>
>>
>

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