Are there any potential pitfalls or security risks when allowing users to input data in PHP without considering case sensitivity?

Allowing users to input data in PHP without considering case sensitivity can lead to inconsistencies in data processing and potential security risks, such as SQL injection attacks or unintended data manipulation. To mitigate these risks, it is important to normalize the input data by converting it to a consistent case (e.g., lowercase) before processing or storing it.

// Normalize user input to lowercase
$userInput = strtolower($_POST['user_input']);

// Use the normalized input in your PHP code
// For example, performing a database query
$query = "SELECT * FROM users WHERE username = '$userInput'";
$result = mysqli_query($connection, $query);