Description
The Kubio AI Page Builder plugin for WordPress is vulnerable to Stored Cross-Site Scripting via kubio/copyright Block Content in all versions up to, and including, 2.8.4 due to insufficient input sanitization and output escaping. 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. This bypasses both the WordPress core kses-on-save filter and the plugin's own wp_kses_post() call, because entity-encoded script tags are treated as inert text by kses but are decoded into live HTML by the subsequent html_entity_decode() call in CopyrightBlock::render_template().
References5
- plugins.trac.wordpress.org/browser/kubio/tags/2.8.2/build/block…
- plugins.trac.wordpress.org/browser/kubio/tags/2.8.2/build/block…
- plugins.trac.wordpress.org/browser/kubio/tags/2.8.2/lib/src/Cor…
- plugins.trac.wordpress.org/changeset?reponame=&old=3616537%40ku…
- www.wordfence.com/threat-intel/vulnerabilities/id/89392f97-58c5…
Metrics
- CVSS 3.1
-
6.4
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 30 · as of 8 November 2026
- CWE
- CWE-79
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.