Re: Exploiting MS Access with SQL Injections

[Paul Johnston <paul.johnston () pentest co uk>]

Hi,

IIRC, Access doesn't have a way of querying what tables exist from SQL
(like INFORMATION_SCHEMA) - to introspection you have to use separate
ADO calls, which isn't possible from an SQL injection. Also, pre-2003
(or so) Access had functions to run command shells and such. However,
Microsoft locked this down considerably (at least, by default) so you're
much more limited now.

I expect you can theoretically extract all the data in this database,
but you'll need to brute force for table and column names, which isn't
for the faint hearted. It may be that extract just some data (e.g. user
names and passwords) would persuade the coder that this is a serious issue.

Paul


On 11/07/2011 22:01, Stealth wrote:
> Alright, so I'm pentesting this box running Windows Server 2003 with
> Microsoft Access as the backend database. It interfaces with this DB via
> the ColdFusion that the app is programmed with (.cfm). The debug error
> messages print out not just the SQL query, but with the surrounding CFM
> code as well as a stack trace, and there are SQL injections riddled all
> throughout the site.
>
> I've never played with MS Access, but I figured this would be
> ridiculously simple. I quickly figured out that it doesn't allow SQL
> code to be executed after the end of a statement ";", which took out a
> lot of exploits. So I decided to poke around some more, possibly map out
> the tables/db's, however almost all of the techniques I knew failed with
> strange Syntax errors I wasn't familiar with. Various attempts at
> researching possible techniques for MS Access resulted in the server
> acting far differently than I was expecting.
>
> I looked into this for a solid 3 hours before deciding to try and see if
> I could find assistance with various DB-exploit programs. I pulled out
> Sqlmap, and it successfully registered the exploit as a valid injection.
> But as soon as I try to pass any flags for pulling information to
> Sqlmap, I get various forms of "This doesn't work with Microsoft
> Access". The only thing I can get SQLmap to do without crashing is
> return the database fingerprint, which I obviously already knew. I'm
> thinking this isn't limitations of the program, but that these
> techniques just don't work on MS Access.
>
> Anyone have any ideas for how I can progress this exploit? The coder
> obviously didn't account for SQL Injection, but I'm thinking there isn't
> anything I can really do here. If anyone has any material to
> read/techniques to try, I'd be grateful.
>
> Thanks guys
>
>
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------------------------------------------------------------------------
Securing Apache Web Server with thawte Digital Certificate
In this guide we examine the importance of Apache-SSL and who needs an SSL certificate.  We look at how SSL works, how 
it benefits your company and how your customers can tell if a site is secure. You will find out how to test, purchase, 
install and use a thawte Digital Certificate on your Apache web server. Throughout, best practices for set-up are 
highlighted to help you ensure efficient ongoing management of your encryption keys and digital certificates.

http://www.dinclinx.com/Redirect.aspx?36;4175;25;1371;0;5;946;e13b6be442f727d1
------------------------------------------------------------------------