All Select Null,null,null,null,null,null,null,null,null-- Vitq — {keyword}' Union

: Combines the results of the original query with a new, malicious query.

: Fills columns with NULL values to match the column count of the original query, which is required for UNION to work. The attacker keeps adding NULL s until the error disappears (often 500 internal server error) and a '200 OK' response is received. : Combines the results of the original query

: A random string identifier often used in automated attacks to verify if the injected query is successfully displayed in the application response. Purpose and Workflow SQL injection UNION attacks | Web Security Academy : Combines the results of the original query