{keyword}') Union All Select Null,null,null,null,null,null,null,null-- Mxyc Site

: Attackers use NULL to figure out exactly how many columns the original database table has. If the number of NULL s matches the columns, the page loads; if not, it crashes.

If a website is vulnerable to this, an attacker doesn't just stop at NULL . They eventually replace those NULL s with commands to extract sensitive info—like your —and display them right on the screen where the "Keyword" results should have been. How Developers Stop This : Attackers use NULL to figure out exactly

: This attempts to "break out" of the developer’s intended code by closing a data field and a function. the page loads