{keyword} Union All Select Null,null,null,null-- Uizf -

: This represents the original search term or input field. The attacker appends the malicious code to this keyword.

: This command tells the database to combine the results of the original query with a new "injected" query. {KEYWORD} UNION ALL SELECT NULL,NULL,NULL,NULL-- Uizf

: The attacker is attempting to determine the number of columns returned by the original database query. By adding NULL values until the page loads without an error, they can identify the table's structure. : This represents the original search term or input field

If you found this in a "complete report" (such as a security scan or a web server log), it indicates that an automated tool or a manual actor has the system. : The attacker is attempting to determine the

: This is a SQL comment symbol. It tells the database to ignore the rest of the original, legitimate query, effectively "breaking" the intended logic to execute the injected code.