$ ping -c1 -p 00b17081bfd8506e86770afa1faeba00 pingb.in
 
$ curl pingb.in/p/b17081bfd8506e86770afa1faeba
 
$ dig b17081bfd8506e86770afa1faeba @pingb.in
 
$ dig b17081bfd8506e86770afa1faeba.ns.pingb.in
 
C:\> nslookup b17081bfd8506e86770afa1faeba pingb.in
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://pingb.in/p/b17081bfd8506e86770afa1faeba">]>
    <foo>&xxe;</foo>
 
Waiting for ping...