Medium · published July 14, 2026
The Ultimate Before After Image Slider & Gallery WordPress plugin before 4.7.1 does not escape the value of the BEAF Slider widget's shortcode field before outputting it on the front end (the value is passed through do_shortcode, which echoes non-shortcode content verbatim), allowing users with administrator-level access to store a script that executes in the browser of any visitor who loads a page displaying the widget.