Routed SQL Injection

I encountered what is known as Routed SQL Injection a couple of times but it was never required to exploit the vulnerability to the full extent. Recently, I discovered an online challenge on the topic and decided to look at it in depth. An explanation of the vulnerability with a vulnerability code which is described in the beginning this post, can be found here . To better understand the vulnerability, lets examine the following piece of code: The magic here is that - the output of the first query is used as the input of the second query and it is the second query which displays output back to us. Or in other words, in order to exploit the SQL Injection vulnerability, we need to control the input for the second query - the variable sec_code (which happens to be the output of the first query). You may have already noticed that, due to the fact that the first query is vulnerable to SQL Injection, we can control and set sec_code to an arbitrary value. Let's exploit t...