What’s Vulnerable › Vulnerabilities

CVE-2026-18488: Blocksy Companion <= 2.1.51 - Authenticated (Author+) Stored Cross-Site Scripting via 'tagName' Block Attribute (blocksy/dynamic-data)

• Severity: medium (CVSS 6.4 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.4% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-09-01 · updated 2026-09-01
• Weakness: CWE-79

Description

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.

Affected products

• creativethemeshq Blocksy Companion: through 2.1.51

References

• 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
• https://plugins.trac.wordpress.org/browser/blocksy-companion/tags/2.1.51/framework/features/blocks/dynamic-data/views/wp-field.php#L487
• https://plugins.trac.wordpress.org/browser/blocksy-companion/tags/2.1.51/static/js/editor/blocks/dynamic-data/block.json#L7
• https://plugins.trac.wordpress.org/changeset/3636709/blocksy-companion/trunk/framework/features/blocks/dynamic-data/views/wp-field.php
• https://plugins.trac.wordpress.org/changeset?old_path=%2Fblocksy-companion/tags/2.1.51&new_path=%2Fblocksy-companion/tags/2.1.52
• https://www.wordfence.com/threat-intel/vulnerabilities/id/e0d0adcc-6741-4cab-aaba-df356691a1ee?source=cve

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