{keyword} Union All Select Null-- Kjag -

The sequence you provided, "{KEYWORD} UNION ALL SELECT NULL-- KJAg" , is a classic example of a . Purpose of the Payload

: This is a SQL comment symbol. It tells the database to ignore the rest of the original query, effectively "breaking" the intended logic to execute the injected command instead. {KEYWORD} UNION ALL SELECT NULL-- KJAg

: An automated scanner or a developer is checking if the input field is properly sanitized. The sequence you provided, "{KEYWORD} UNION ALL SELECT

This specific string is typically used by security researchers or attackers to test for vulnerabilities in a web application's database interactions. The sequence you provided