{keyword}') Union All Select Null,null,null,null,null,null,null,null,null-- Zljd May 2026

: Use a WAF to detect and block common SQLi patterns (like UNION ALL SELECT ) before they reach your server.

The string you provided is a classic example of a . This specific snippet is designed to exploit a vulnerability in a database-driven application to bypass security filters and extract unauthorized data. : Use a WAF to detect and block

To protect an application from this specific type of attack, developers should follow these industry-standard practices: To protect an application from this specific type

: Only allow expected characters (e.g., alphanumeric only for a username). For a UNION attack to work, the second

: In some configurations, attackers can run commands to delete tables or modify sensitive financial records. ✅ How to Prevent This

: These are placeholders. For a UNION attack to work, the second query must have the exact same number of columns as the first. Attackers use NULL to test and match the column count without causing data type errors.

: This is the SQL comment symbol. It tells the database to ignore everything that follows it in the code, effectively "muting" the rest of the original, legitimate query.