WordPress Magazine Companion Plugin Stored Cross-Site Scripting Vulnerability

A stored cross-site scripting vulnerability has been identified in the Magazine Companion plugin for WordPress, affecting all versions through 1.2.3. The issue arises in the bnm-blocks/featured-posts-1 block, where the 'headerHtmlTag' attribute does not properly sanitize user input or escape output. This flaw allows authenticated attackers with contributor-level access or higher to inject arbitrary scripts into pages, which are executed when users view the affected page.

Impact

Exploitation of this vulnerability allows for stored cross-site scripting, where injected scripts are executed in the context of the user viewing the page.