The Ultimate Carousel For WPBakery Page Builder WordPress plugin through 2.6 does not validate and escape some of its shortcode attributes before outputting them back in a page/post where the shortcode is embed, which could allow users with the contributor role and above to perform Stored Cross-Site Scripting attacks.
https://wpscan.com/vulnerability/7ba7849d-e07b-465a-bfb7-10c8186be140