{keyword} Union All Select Null,null,null,null,null,null,null,null-- Ppsq Page

: Attackers use NULL because it is compatible with almost every data type (integers, strings, dates), making it the "safest" way to avoid syntax errors while testing column counts.

The string you provided is a classic payload. It is not a feature of a specific software product but rather a technique used by security researchers and attackers to probe databases for vulnerabilities. Purpose of the Payload : Attackers use NULL because it is compatible

: This represents the original input (like a product category or search term) that the application expects. Purpose of the Payload : This represents the

: When the number of NULL s matches exactly (in your case, 8 columns), the page will load normally or show an extra blank row, confirming the database structure. Why This Matters : An attacker starts with one NULL and keeps adding more (e

: If the number of NULL values does not match the original query's column count, the server usually returns an error (like a 500 Internal Server Error).

: An attacker starts with one NULL and keeps adding more (e.g., NULL, NULL , then NULL, NULL, NULL ).

Once an attacker knows there are 8 columns, they can replace the NULL values with commands to extract sensitive data, such as usernames, passwords, or database versions. SQL injection UNION attacks | Web Security Academy