CVE-2026-18488

MediumCVSS 6.4

Published: 01/09/2026(UTC)Updated: 01/09/2026(UTC)Translated: 01/09/2026(UTC)NVD NIST

Exploitation Probability (EPSS)

Low risk

0.33%

26th percentile - higher than 26% of all known CVEs

Summary

The Blocksy Companion plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'tagName' block attribute in all versions up to and including 2.1.51. Authenticated attackers with author-level access or higher can inject arbitrary web scripts that execute whenever a user accesses an injected page.

Risk Assessment

The risk includes user data theft, account takeover, and malware distribution on the site, potentially harming the organization's reputation.

Recommendation

Update the plugin to the latest patched version. Also, restrict author permissions and regularly audit content for malicious code.

Other vulnerabilities in Blocksy Companion

CVE-2026-15158Critical
The Blocksy Companion plugin for WordPress is vulnerable to arbitrary file upload in versions up to 2.1.46. The flaw lies in the save_attachments function, which improperly validates file extensions, allowing double-extension files like shell.woff2.php to bypass MIME checks. This can lead to remote code execution, but exploitation requires the premium plugin with specific extensions active.

Original NVD description (English source)

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.