CVE-2026-6378: CKP267 Maxiblocks Builder | 17,000+ Design Assets, Patterns, Icons & Starter Sites

Medium severity, CVSS 6.4. EPSS: 0.4% chance of exploitation in the next 30 days.

The Maxi Blocks plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the `/wp-json/maxi-blocks/v1.0/style-card` REST API endpoint in all versions up to, and including, 2.1.9 due to insufficient input sanitization and output escaping of the `sc_styles` parameter. This makes it possible for authenticated attackers, with Author-level access and above, to inject arbitrary web scripts that execute on every page where the plugin's style card styles are loaded, including across the entire WordPress admin panel.

Affected products

• CKP267 Maxiblocks Builder | 17,000+ Design Assets, Patterns, Icons & Starter Sites: up to and including 2.1.9

Published 2026-05-02. Last modified 2026-06-17.