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

: 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.

: 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 : Fills columns with NULL values to match

This SQL injection payload ( ' UNION ALL SELECT NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL-- vITQ ) is a classic technique used in to determine the exact number of columns returned by a vulnerable web application's original database query. Payload Breakdown ' : Closes the original SQL statement's string parameter. Purpose and Workflow SQL injection UNION attacks |