通过AJAX发送HTML并保存在MySQL数据库中的安全隐患

How should I be properly securing the transfer of large sections of HTML via AJAX and then storing in the WordPress database as a post_meta field? The HTML would be around 100-500kb.

Below is the code I am using to send the HTML. I think that the storing of it will not be such an issue as I am more adept at PHP, but I am wondering about XSS and the like when using Javascript.

Is this a safe way to do this? What steps do I need to take to secure this? It will be behind a paid login, so that will reduce any threats a fair bit.

$('#save-report').on( 'click', function( e ){

    e.preventDefault();

    var $url = $( '#save-report' ).data( 'url' );
    var $report = $( '#report-wrapper' ).html();

    jQuery.ajax({
        url: zee.ajax_url,
        data: {
            action : 'zee_save_report',
            report : $report,
            url : $url,
            nonce : zee.nonce
        },
        type: 'post',
        dataType: 'json',
        success : function(response) {
            console.log(response)
            return false;
        }
    });

});