The Photo Gallery by 10Web WordPress plugin before 1.8.44 does not escape two request parameters before reflecting them into input-attribute values on its admin pages (one on the Shortcode page, one on the Galleries/Albums list page), so an unauthenticated attacker can craft a link that, when opened by a logged-in administrator (or, for the first sink, a contributor), executes arbitrary JavaScript in the victim's authenticated session via an auto-firing onfocus handler. The Galleries/Albums sink renders only when the site has more than 20 galleries/albums (the normal state of a populated install).