Identifying a blind SQL Injection

We already saw how a SQL Injection vulnerability works. In this recipe, we will cover a different type of vulnerability of the same kind, one that does not show any error message or hint that could lead us to the exploitation. We will learn how to identify a blind SQLi.

How to do it...

1. Log into DVWA and go to SQL Injection (Blind).

2. It looks exactly the same as the SQL Injection form we know from a previous recipe. Introduce a 1 in the text box and click Submit.

3. Now, let's do our first test with 1':

   

   We get no error message, but no result either; something interesting could be happening here.

4. We do our second test with 1'':

   

   The result for ID=1 is shown, this means that the previous tests (1') resulted in an error that was captured and processed by the application. It's highly probable that we have an SQL Injection here, but it seems to be blind, no information about the database is shown, so we will need to guess.

5. Let's try to identify what happens when the user injects...