In PHP, what are the implications of storing POST data in sessions for form processing and validation?

Storing POST data in sessions for form processing and validation can lead to security vulnerabilities as it can be tampered with by the user. It is recommended to validate and sanitize the POST data before storing it in the session. One way to solve this issue is to store only the validated and sanitized data in the session for later use. 

// Validate and sanitize the POST data
$validated_data = filter_input_array(INPUT_POST, [
    'username' => FILTER_SANITIZE_STRING,
    'email' => FILTER_VALIDATE_EMAIL,
]);

// Store the validated data in the session
$_SESSION['validated_data'] = $validated_data;

Related Questions