Gutentools WordPress Plugin Stored Cross-Site Scripting Vulnerability

A stored cross-site scripting vulnerability has been identified in the Gutentools WordPress plugin, affecting all versions through 1.1.3. The issue arises in the Post Slider block, where the block_id attribute lacks proper input sanitization and output escaping. This flaw allows authenticated attackers with Contributor-level access or higher to inject arbitrary scripts into pages, which are executed when users view the injected content.

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 a Post Slider block and inject a script into the block_id attribute. Once the block is saved, the injected script will execute when the page is viewed.

Remediation

Users are advised to update the Gutentools WordPress plugin to version 1.1.4 or later.