The best recommendation to remediate this vulnerability is to use parameterized queries in the web application. Parameterized queries are a way of preventing SQL injection attacks by separating the SQL statements from the user input. This way, the user input is treated as a literal value and not as part of the SQL statement. For example, instead of using x' OR role LIKE '%admin%, the user input would be passed as a parameter to a prepared statement that would check if it matches any value in the database.