Vulnerability in Blocksy Companion — CVE-2026-18488

What to do now

Update Blocksy Companion to 2.1.52 or later.

Affected versions

• Everything up to and including 2.1.51

The Blocksy Companion plugin for WordPress is vulnerable to Stored Cross-Site Scripting via 'tagName' Block Attribute (blocksy/dynamic-data) in all versions up to, and including, 2.1.51 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with author-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

This description is reproduced verbatim from the public vulnerability record.

• https://plugins.trac.wordpress.org/browser/blocksy-companion/tags/2.1.4/framework/features/blocks/dynamic-data/block.php#L183
• https://plugins.trac.wordpress.org/browser/blocksy-companion/tags/2.1.4/framework/features/blocks/dynamic-data/views/wp-field.php#L448
• https://plugins.trac.wordpress.org/browser/blocksy-companion/tags/2.1.4/framework/features/blocks/dynamic-data/views/wp-field.php#L487
• https://plugins.trac.wordpress.org/browser/blocksy-companion/tags/2.1.4/static/js/editor/blocks/dynamic-data/block.json#L7
• https://plugins.trac.wordpress.org/browser/blocksy-companion/tags/2.1.51/framework/features/blocks/dynamic-data/block.php#L183
• https://plugins.trac.wordpress.org/browser/blocksy-companion/tags/2.1.51/framework/features/blocks/dynamic-data/views/wp-field.php#L448

This page is compiled automatically from public databases. Accuracy is not guaranteed; confirm against the vendor advisory before acting.