Akeeba Ticket System is explicitly designed to NOT let Guest users file tickets. It is insecure. Anyone who is NOT logged in to your site (either a person or a malicious bot written by a hacker) can see all tickets filed by ALL guest users and read them, download any attachments (posted by the user or yourself), edit posts, close them, or post as a user. There is absolutely no security or accountability. Asking people to submit their email address in a custom field is even worse because now their email address is posted on the open Internet.
And no, not having a public link to the page listing all the tickets isn't much of a solution. It's trivial to access index.php?option=com_ats&view=Categories to list all categories or index.php?option=com_ats&view=Ticket&id=1 (and monotonically increase the ID) to read all tickets. Remember that if you can get the URL to a ticket the only thing standing between you and the ticket is Joomla's access control. You have nullified that by allowing guest users to post tickets, therefore you have NO SECURITY WHATSOEVER FOR YOUR GUEST TICKETS. Sorry for the shouting, I cannot stress enough how bad this is for security and privacy.
All things considered, it's better having people register a free to your site before filing a ticket (in a category locked to the Registered group, NOT Guest!) or using a Facebook page (where at least there's a modicum of accountability).
Nicholas K. Dionysopoulos
Lead Developer and Director
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