{keyword}') Union All Select Null,null,null,null,null,null,null,null-- Mxyc May 2026

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

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 : This attempts to "break out" of the

: This is the heart of the attack. It tells the database to combine the results of the original (legitimate) search with a new set of data the attacker wants to see. How Developers Stop This : This is the heart of the attack

The text ') UNION ALL SELECT NULL,NULL...-- is a malicious payload used to test for vulnerabilities in a database. Here is a look into what that string

Here is a look into what that string is designed to do and why it’s a fundamental concept in web security. What is this string?

: 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.