CVE-2026-75016: Magazine Blocks <= 1.8.6 - Authenticated (Contributor+) Stored Cross-Site Scripting via 'clientId' Block Attribute
The Magazine Blocks plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the News Ticker block's clientId attribute in versions up to, and including, 1.8.6. This is due to insufficient input sanitization and output escaping in the NewsTicker::render() method, which concatenates the clientId block attribute into an HTML class attribute without applying escattr(). 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.
Affected Software
Event History
Frequently Asked Questions
Who can exploit this issue?
An attacker needs an authenticated WordPress account with Contributor-level access or higher. They must be able to inject a crafted clientId attribute into a News Ticker block on a page.
When does the injected code run?
The injected script executes when a user accesses the page containing the crafted News Ticker block. This can affect other users who view that page.
How can I determine whether my site is affected?
Sites using Magazine Blocks version 1.8.6 or earlier are affected. Review News Ticker blocks and their clientId attributes for unexpected or malformed values, particularly on pages editable by Contributor-level users or above.