The Page Builder: KingComposer plugin for WordPress is vulnerable to Stored Cross-Site Scripting via via shortcode in versions before 2.9.4 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

The Page Builder: KingComposer plugin for WordPress is vulnerable to authorization bypass in versions up to, and including, 2.9.3. This is due to a security nonce being leaked in the '/wp-admin/index.php' page. This makes it possible for authenticated attackers to change arbitrary WordPress options, delete arbitrary files/folders, and inject arbitrary content.

The KingComposer WordPress plugin through 2.9.6 does not have authorisation, CSRF and sanitisation/escaping when creating profile, allowing any authenticated users to create arbitrary ones, with Cross-Site Scripting payloads in them

The Page Builder KingComposer WordPress plugin through 2.9.6 does not validate the id parameter before redirecting the user to it via the kc_get_thumbn AJAX action available to both unauthenticated and authenticated users

A reflected Cross-Site Scripting (XSS) Vulnerability in the KingComposer plugin through 2.9.4 for WordPress allows remote attackers to trick a victim into submitting an install_online_preset AJAX request containing base64-encoded JavaScript (in the kc-online-preset-data POST parameter) that is executed in the victim's browser.

The kingcomposer plugin 2.7.6 for WordPress has wp-admin/admin.php?page=kc-mapper id XSS.