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
: 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 string is a classic example of a
: 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
