v 2.3.8, same PoC than 

v 2.3.9 (can only delete arbitrary documents from the plugin)
1 - Login as a subscriber and view the source of the backend page.
2 - Search for `eazydocs_local_object` variable.
3 - Inside the variable, you will find the option tag containing the _wpnonce and the post id.
4 - Change the value of the following URL with the data from step 3:<_wpnonce>&DeleteID=<post_id>