The kvCORE IDX plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via any parameter on pages with the kvcoreidx_listings_sitemap_ranges, kvcoreidx_listings_sitemap_page, kvcoreidx_agent_profile_sitemap, or kvcoreidx_agent_profile shortcode present in all versions up to, and including, 2.3.35 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link.
The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.