What the vulnerability does
01Description
The Ultimate Blocks – WordPress Blocks Plugin plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the plugin's tab anchor metabox in all versions up to, and including, 3.0.8 due to insufficient input sanitization and output escaping on user supplied attributes. This makes it possible for authenticated attackers with contributor-level and above permissions to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.
Explanation of Vulnerability in Simple Terms
02Summary
Ultimate Blocks contains a cross-site scripting (XSS) vulnerability in versions up to 3.1.0. An authenticated user with low privileges can inject malicious scripts that execute in the browsers of other site users, including administrators. The vulnerability affects the block editor and can compromise site security and user data.
What an attacker can do
03Attacker Capabilities
Inject malicious JavaScript that runs in other users' browsers, including administrators.
Potential impact on your site
04Site Impact
Attackers with contributor or editor access can steal admin credentials, modify site content, or compromise visitor data.
Conditions required to exploit
05Prerequisites
Attacker must have a low-privilege authenticated account on the WordPress site.
Key dates
06Disclosure timeline
June 19, 2024
CVE published
April 8, 2026
Record updated
