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

: Confirm that the application is vulnerable to SQL injection.

: This represents the original search term or input field. The attacker appends the malicious code to this keyword. {KEYWORD} UNION ALL SELECT NULL,NULL,NULL,NULL-- Uizf

: In some cases, these injections can be used to log in without a valid password. : Confirm that the application is vulnerable to

This string is a classic example of a , specifically a Union-Based SQLi attack . It is used by attackers to test for vulnerabilities or extract data from a database. Breakdown of the Payload : In some cases, these injections can be

: 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.

: Once the column count is known, they replace the NULL values with actual commands (e.g., version() , user() , or table_name ) to steal sensitive information.

: 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.