Select Null,null,null,null,null-- Bwmv - {keyword}' Union All

: This is the core of the attack. It tells the database to append the results of a second query to the results of the first one.

: A WAF can automatically block requests containing common injection patterns like UNION SELECT . {KEYWORD}' UNION ALL SELECT NULL,NULL,NULL,NULL,NULL-- bWmV

: This attempts to "break out" of a standard text input field in a web application by closing the developer's intended SQL query quote early. : This is the core of the attack

: This is likely a random "cache-buster" or unique identifier used by automated security scanners (like Burp Suite or Acunetix) to track which specific payload triggered a response. Why you are seeing this : This attempts to "break out" of a

: This ensures the database treats input as data only, never as executable code.

: The attacker is trying to determine how many columns the original database table has. If the number of NULL values doesn't match the number of columns in the original query, the database will return an error. By adding or removing NULL s, an attacker can find the exact table structure.