Simple Divi Shortcode <= 1.2 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'id' Shortcode Attribute

Summary

The Simple Divi Shortcode plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'id' parameter of the [showmodule] shortcode in versions up to, and including, 1.2 This is due to insufficient input sanitization and output escaping in the showmodule_shortcode() function, which concatenates the 'id' shortcode attribute directly into a dynamically constructed shortcode string without applying esc_attr() or any escaping, allowing an attacker to break out of the attribute context and inject arbitrary HTML. This makes it possible for authenticated attackers, with contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.