Ultimate Blocks WordPress Plugin Stored Cross-Site Scripting Vulnerability

A stored cross-site scripting vulnerability has been identified in the Ultimate Blocks WordPress Blocks Plugin, affecting all versions through 3.3.3. The issue arises from inadequate input sanitization and output escaping, allowing authenticated attackers with Contributor-level access or higher to inject arbitrary scripts into pages. These scripts are executed when users access the affected pages.

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 inject scripts through multiple vulnerable widgets. The injected scripts will be executed when the page is accessed by any user.

Remediation

Users are advised to update the Ultimate Blocks WordPress Blocks Plugin to version 3.3.4 or later.