The Post Grid, Slider & Carousel Ultimate – with Shortcode, Gutenberg Block & Elementor Widget plugin for WordPress is vulnerable to Local File Inclusion in all versions up to, and including, 1.6.10 via the 'theme' parameter of the post_type_ajax_handler() function. This makes it possible for authenticated attackers, with Contributor-level access and above, to include and execute arbitrary files on the server, allowing the execution of any PHP code in those files. This can be used to bypass access controls, obtain sensitive data, or achieve code execution in cases where images and other “safe” file types can be uploaded and included.

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in wpWax Post Grid, Slider & Carousel Ultimate allows Stored XSS.This issue affects Post Grid, Slider & Carousel Ultimate: from n/a through 1.6.6.

The Post Grid, Slider & Carousel Ultimate – with Shortcode, Gutenberg Block & Elementor Widget plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 1.6.7 via deserialization of untrusted input in the outpost_shortcode_metabox_markup function. This makes it possible for authenticated attackers, with contributor-level access and above, to inject a PHP Object. If a POP chain is present via an additional plugin or theme installed on the target system, it could allow the attacker to delete arbitrary files, retrieve sensitive data, or execute code.

The Post Grid, Slider & Carousel Ultimate WordPress plugin before 1.5.0 does not sanitise and escape the Header Title, which could allow high privilege users to perform Cross-Site Scripting attacks even when the unfiltered_html capability is disallowed.