Essential Blocks WordPress Plugin Stored Cross-Site Scripting Vulnerability

A stored cross-site scripting vulnerability has been identified in the Essential Blocks WordPress plugin, specifically in the Gutenberg Blocks, Patterns & Templates version 6.0.4 and prior. The issue arises in the 'Add to Cart' block due to inadequate output escaping in the render_callback function. This vulnerability allows authenticated attackers with Contributor-level access and above to inject arbitrary scripts that execute 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.

Reproduction

To reproduce this vulnerability, an authenticated user with Contributor-level access or higher can add an 'Add to Cart' block. By including a script in the className, classHook, or blockId attributes, the injected script will be executed when the page is viewed.

Remediation

Users are advised to update the Essential Blocks WordPress plugin to version 6.1.0 or later.