In the previous articles, I mentioned how easy it was for me
to obtain my administrator’s right simply by social engineering the IT support
department. However, that doesn’t not solve ALL the problems we have. It is
good to have a laptop with an additional local admin account, but it is not
enough to simply have that. There are still other helpless laptops out there.
Ultimately, what I wanted was the admin account so that I can help them out
too.
While I have my admin rights, it’s easy and simple to just
change the password of the admin account to whatever I like, but that’s not my
aim. I also realized that in order to push my hacking tools onto the laptop to
extract the password hash, I will probably have to disable or uninstall the
antivirus system because it is basically blocking and deleting my software
whenever I copy it in.
Touching the antivirus is probably not where I want to go.
Basically, messing with the antivirus may trigger some audit alarms which will
not look nice on me. Secondly, I may not be able to properly uninstall or
install the antivirus back because it may have a secondary password or some
required files for the group policy. Enterprise level antivirus usually has all
these additional stuffs. Destroying the antivirus will be a last resort for me.
Just to recall in the first article, the hard disk has a
disk based encryption and that is why I am unable to use a boot disk or boot CD
to extract the password hash. In short,
I am pretty screw if I continue in this path to try to extract the password
hash. In a separate thread, I did manage to break one of these systems using a
floppy boot up, but that’s another story. I had another thought. That is to
install the system console and boot that up. But the chances that I will be
able to run or do anything else in that restricted shell is quite close to none.
So, what will be better than the password hash? Answer : The password itself.
So, how can one get the password? Let’s backtrack this a
bit. How does the IT department upgrade and change all our passwords? Typically
if you work smart, you will either push it down a GPO or use some sort of batch
processing, maybe even SMS or WUSS. Now, being such a huge enterprise, I would
guess they would use at least one of these. I strike GPO off because the admin
account is a local account. So, what I will do is to find out how they changed
the password (in batch).
I do not know why, but my IT department like to leave a link
to their software repository around on their desktop. I guess that’s probably
the root of corporate piracy if any happens here. In any case, this is the
place I would start. Looking through the folders, I basically had gone through
these times to times for other reasons, so pretty much know which are the new
stuffs, or simply just sort them by date. Then from the new folders, I found
another link to another server which contains the new software sets for this
upgrade. Now, this will contains the binaries for the antivirus. I almost
thought that I would reconsider breaking the antivirus and reinstalling it back
using these binaries. Until I saw a very obvious file in the root
directory. It sound like jackpot. In
fact, there is even a file call “ChangePasswordforXXX.exe” lying around there
for the picking. Bingo.
So, this is a exe file. I would like to break it apart using
IDA Pro or other debugger, but just throwing at a long shot, I thought I would
start with a text editor instead. Based on my experience, most people do not
encrypt or even obfuscate their binary. I had been able to break many
applications and website basically because the binaries is not protected.
Again, this enables me to accomplish what I did. By looking through the binary
file, I notice this is a simple WISE installation binary. Yes, actually I
already knew that when I saw the icon. They did not even bothered to change it.
WISE has tendency to leave some of the configuration in clear text even when it
is compiled into a binary. That is the reason why I saw the things I saw
without even the use of a debugger. Somewhere in the file, I saw the password I
was looking for. In fact, I did not even really take a look at the file, I
simple do a search for “password” and I am brought to that offset in the file.
The password was long, complex and consists of alphanumeric
with upper and lower case and symbols. But it is just another password hacked
by me today.
As an added bonus, I even got hold of an additional password
in the file just right below it. It is the encryption password for the
harddisk. I haven’t figured out how I could use it, but I guess it will
probably be useful, someday.
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