RE: SQL Injection Basics

["Dennis Hurst" <dhurst () spidynamics com>]

Nick,

It really doesn't matter if the developer used tick marks or not, just
if you can inject something the developer didn't plan for into the SQL
string. If an extra tick (and many other character combinations) gets
injected anywhere in the string you will have SQL Injection issues.

If the developer does not parse for unexpected strings there are
probably issues, regardless of what the SQL statement looks like.

Have a great day,

Dennis Hurst
dhurst () spidynamics com
SPI Labs



-----Original Message-----
From: Nick Jacobsen [mailto:nick () ethicsdesign com] 
Sent: Monday, February 10, 2003 4:38 PM
To: dhurst () spidynamics com; webappsec () securityfocus com
Subject: Re: SQL Injection Basics


Right, I wasn't thinking too well...  makes sense.  Though, according to
quite a few SQL injection faqs I have read, it said that you could only
inject code if the developer used tick marks.  However, I just recently
used
SQL injection on some code where the developer used NO tick marks, but
injection still worked if the injection string contained TWO tick marks.
Was this just a fluke, or is it something that the faqs had wrong?

Nick J.
nick () ethicsdesign com

----- Original Message -----
From: "Dennis Hurst" <dhurst () spidynamics com>
To: "'Nick Jacobsen'" <nick () ethicsdesign com>
Cc: <webappsec () securityfocus com>
Sent: Monday, February 10, 2003 8:59 AM
Subject: RE: SQL Injection Basics


> Nick,
>
> Good question, but SQL Injection is absolutely an issue in VBScript
(ASP
> pages).  Here's the deal, the ' only acts as a comment if it's in the
> source code, not when it's in a variable. So...
>
>
> If you have code that looks like this:
>
> Dim sSql, rs, oConnection
>
> '..... Setup the connection......
>
> sSql = "Select * from myCustomers where FirstName = '" &
> Request("txtFirstName") & "'"
>
> Set rs = oConnection.Execute(sSql)
>
> '.....do something with the returned data.....
>
>
> And a user puts a ' in the text box called txtFirstName you end up
with
> something that acts like this:
>
> Dim sSql, rs, oConnection
>
> '..... Setup the connection......
>
> sSql = "Select * from myCustomers where FirstName = '''"
>
> Set rs = oConnection.Execute(sSql)
>
> '.....do something with the returned data.....
>
>
>
>
>
> Have a great day,
>
> Dennis Hurst
> dhurst () spidynamics com
> SPI Labs
>
>
>
> -----Original Message-----
> From: Nick Jacobsen [mailto:nick () ethicsdesign com]
> Sent: Monday, February 10, 2003 6:07 AM
> To: Loki; raul.johhut () hushmail com
> Cc: webappsec () securityfocus com
> Subject: Re: SQL Injection Basics
>
>
> Hmm...  just a gues here, but if a developer is using VBScript as the
> scripting language, would SQL injection be impossible, since in
VBScript
> the
> " ' " mark is a comment mark, and therefore never used in SQL
> statements?
>
> Nick J
> nick () ethicsdesign com
>
> ----- Original Message -----
> From: "Loki" <loki () fatelabs com>
> To: <raul.johhut () hushmail com>
> Cc: <webappsec () securityfocus com>
> Sent: Saturday, February 08, 2003 9:16 PM
> Subject: Re: SQL Injection Basics
>
>
> > Raul:
> >
> > SQL injection is not replacing the userid field in the url with
> "sdfsd",
> > its escaping an SQL query with a single tick (') that the developer
> > doesn't escape (or in the case of PHP, GLOBALS is turned on in the
> > php.ini).
> >
> > SQL injection is simply altering the SQL query sent to the SQL
server
> > and executing an a malicious query instead of what was expected by
the
> > developer. Depending on the remote server (Oracle, Microsoft SQL,
> MySQL,
> > PostgreSQL), these statements will only differ based on their stored
> > procedures. Microsoft SQL containing the more fun procedure of
> > (xp_cmdshell) :)
> >
> > e.g.
> >
> > 'SELECT * FROM USERS
> > Username: ' or 1=1--
> >
> >
> > There are several papers available on SQL injection attacks, one in
> > particular written by Chris Anley at
> > http://www.nextgenss.com/research/papers.html
> >
> > Typically, you can quickly check web apps for vulnerability to
> injection
> > by just entering a single tick (') in the form submission field,
> hitting
> > submit, and looking for any errors such as ODBC, etc.
> >
> >
> >
> > Loki
> > Fate Research Labs
> > www.fatelabs.com
> >
> >
> >
> > On Sat, 2003-02-08 at 20:21, raul.johhut () hushmail com wrote:
> > > I am pen testing a webapp and am having some problems with SQL
> injection.
> > > The app creates an ODBC error. Is this a garuntee of SQL Injection
?
> > > If I use www.victim/test.asp?userid=sfdsd
> > >
> > > the error is "inncorrect syntax near line 28 of test.asp" (or
thats
> the
> English translation equiv in my case).
> > > I know the database is called master, and has a table test. What
is
> the
> syntax I should use ?
> > > What are the best freeware and open source tools for testing SQL
> injection ? I tried WPosion which was OK.
> > > I also tried WebSleuth (which seems to have gone from GPL to
closed
> source commercial btw). Am I right is saying that the SQL plugin has
to
> connect directly to the database to work ? I can only see port 80 so
> don't
> think this will work ?
> > > Thanks, Raul.
> > >
> > >
> > >
> > > Concerned about your privacy? Follow this link to get
> > > FREE encrypted email: https://www.hushmail.com/?l=2
> > >
> > > Big $$$ to be made with the HushMail Affiliate Program:
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> > --
> > Loki <loki () fatelabs com>