The Orders Tracking for WooCommerce WordPress plugin before 1.2.6 doesn't validate the file_url parameter when importing a CSV file, allowing high privilege users with the manage_woocommerce capability to access any file on the web server via a Traversal attack. The content retrieved is however limited to the first line of the file.
https://wpscan.com/vulnerability/8189afc4-17b3-4696-89e1-731011cb9e2b