Waraxe IT Security Portal

d3a2d3e3 · Beginner

I have been lurking on this site for awhile. Decided to register and participate. The current challenge before me might be easy for some of you, so here goes:

Target is running vBulletin 3.8.1 with an exploitable vbseo 3.1.0 which is a nice start. The local file include vulnerability of vbseo 3.1.0 is the exploit of choice. There are, however, challenges to this:

First, the admin is no idiot, so he has all attachments disabled (can't attach documents, photos, text files, etc to your posts). This means tossing a nice PHP based shell into a text file and attaching it will not work.

Second, you can upload an avatar, a profile picture, and create your own photo albums within vB, but so far I have been unable to hide code in the images I upload through those options because the image processor (GD or ImageMagick - I am not sure which) is intelligent enough to see it is not a valid image file I am uploading.

* If someone has a good idea on how to hide code in the images, I would love to hear it.

Next, I thought about the Infernoshout the site is running. What if I could post some code in chat, then get it to execute? I tested the vbseo LFI vulnerability, and it allows me to view the shoutbox contents even when not logged in. It shows those contents in somewhat of an XML type of look. Since I can use the vbseo LFI vulnerability to see what is in the shoutbox even when not logged in (usually you must be logged in to see shoutbox contents), it seems to me that embedding code in a "shout" could be my ticket to sneaking something through the door so to speak. Expanding upon that, here's the next issue: the shoutbox will not let you post < or > as it will convert them to an alternate kind of text. Without < or > it is hard for me to call out a PHP command, for instance.

* If someone has a good idea on how to obfuscate the < and > in the shoutbox so I can successfully put PHP code in a shout, then I'd have a chance of making this work.

Any ideas on either of the * items I'm facing would be much appreciated!

d3a2d3e3 · Beginner

Here is the URL that I use to get the vbseo LFI vulnerability to allow me to view the shoutbox contents even when not logged into the site (normally you must be logged into this particular target in question to view the shoutbox contents):

http://www.[target].com/[forumpath]/vbseo.php?vbseoembedd=1&vbseourl=infernoshout.php

When I use Firefox to view the above URL, I get this message:

This XML file does not appear to have any style information associated with it. The document tree is shown below.

With this content below the message: