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

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.

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 {KEYWORD} UNION ALL SELECT NULL,NULL,NULL,NULL-- Uizf