{keyword}') Union All Select Null,null,null,null,null,null,null-- Hofz Apr 2026

: The attacker uses NULL values to figure out how many columns are in the original database table. If the number of NULL s doesn't match the number of columns in the original query, the database will return an error.

: This is the core of the attack. It tells the database to combine the results of the legitimate query with the results of a new, malicious one.

: A WAF can often block these types of patterned attacks automatically. : The attacker uses NULL values to figure

: This part attempts to "break out" of a standard SQL query. It uses a closing quote and parenthesis to terminate whatever the original developer intended the query to do.

: Ensure all data entered by users is cleaned and validated before it hits your database. It tells the database to combine the results

Are you seeing this in your , or are you testing the security of your own code ?

The string you provided is a . Specifically, it is designed to exploit a vulnerability in a database-driven application to extract unauthorized data. It uses a closing quote and parenthesis to

: Use parameterized queries so that user input is never executed as code.