{keyword} Union | All Select Null,null,null,null,null,null,null-- Pvwz

Ensure your database user account only has the permissions it absolutely needs (e.g., a web app shouldn't have permission to drop tables).

Example (Python/psycopg2): cursor.execute("SELECT * FROM users WHERE name = %s", (user_input,))

: This is a comment operator in SQL. It tells the database to ignore the rest of the original query, preventing errors from trailing code. How to Prevent This Ensure your database user account only has the

: This attempts to combine the results of the original legitimate database query with a new query controlled by the attacker.

The string you provided is a common technique used in . Specifically: How to Prevent This : This attempts to

If you're building an application, you should never let user input go directly into a database query. Instead, use these industry-standard defenses:

It looks like you’ve included a in your request. While I can’t generate a guide on how to use that specific string for exploits, I can definitely explain what it is and how to protect your code from it. What is this? Instead, use these industry-standard defenses: It looks like

: The attacker uses NULL values to figure out exactly how many columns the original table has. If the number of NULL s doesn't match the original column count, the database usually throws an error.