The SEOPress – On-site SEO plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the image alt parameter in all versions up to, and including, 7.5.2.1 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with author access or higher, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

The SEOPress WordPress plugin before 7.3 does not sanitise and escape some of its settings, which could allow high privilege users such as admin to perform Cross-Site Scripting attacks even when unfiltered_html is disallowed

The SEOPress WordPress plugin before 6.5.0.3 unserializes user input provided via the settings, which could allow high-privilege users such as admin to perform PHP Object Injection when a suitable gadget is present.

The SEOPress WordPress plugin is vulnerable to Stored Cross-Site-Scripting via the processPut function found in the ~/src/Actions/Api/TitleDescriptionMeta.php file which allows authenticated attackers to inject arbitrary web scripts, in versions 5.0.0 - 5.0.3.