The tweet shares a custom AWS WAF regex pattern set designed to detect and block a specific SQL Injection (SQLi) bypass technique. This bypass involves mutated SQL operators like logical OR (||), logical AND (&&), the NULL-safe equality operator (<=>), combined with other symbols such as ';&&' and numeric sequences like '1-1'. These mutated operators are used by attackers to evade standard WAF SQLi detection rules.

The provided regex pattern is: (?:\s*\|\|\s*|\s*&&\s*|<=>\s*|;&&|1-\d). This pattern matches occurrences of those mutated operators even if surrounded by spaces.

To implement this protection, create a custom regex pattern set in your AWS WAF WebACL using this pattern, set the action to block, and assign it a priority higher than existing managed rules. This will help AWS WAF to detect and block SQL injection attempts using these mutated operators that otherwise may bypass default protections.

In summary, this method enhances SQLi defense by targeting known mutated operator bypass techniques through a precise regex in custom AWS WAF rules.