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It sounds like you want to store the file in Drupal's private file system.  There is no need for a module - this is in core.
Files that are in the private system will:

Be protected from access by Drupal's core access control system. If the user don't have access to the page where the file field is attached, he/she will not have access to  the file.
The URL will not be generally usable. (i.e. the link will be displayed in the browser's  address field, but only works &quot;inside&quot; Drupal).
If you place your private files outside the webroot (strongly recommended), they can only be accessed through Drupal's access control system. There is no real URL that can be guessed.

There is plenty of tutorials about setting up and using a private file system in Drupal [GIYF].  Here is a link to one example:
https://www.cmsdrupal.com/blog/how-secure-private-files-drupal-tips-safely-configuring-your-file-system