CVE-2026-3995

Description

The OPEN-BRAIN plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'API Key' settings field in all versions up to, and including, 0.5.0. This is due to insufficient input sanitization and output escaping. The plugin uses sanitize_text_field() which strips HTML tags but does not encode double quotes or other HTML-special characters needed for safe attribute context output. The API key value is saved via update_option() and later output into an HTML input element's value attribute without esc_attr() escaping. This makes it possible for authenticated attackers, with Administrator-level access, to inject arbitrary web scripts via attribute breakout payloads (e.g., double quotes followed by event handlers) that execute whenever a user accesses the plugin settings page.

CVSS Vector

References

• https://plugins.trac.wordpress.org/browser/open-brain/tags/0.5.0/index.php#L128
• https://plugins.trac.wordpress.org/browser/open-brain/tags/0.5.0/index.php#L252
• https://plugins.trac.wordpress.org/browser/open-brain/tags/0.5.0/index.php#L253
• https://plugins.trac.wordpress.org/browser/open-brain/tags/0.5.0/index.php#L272
• https://plugins.trac.wordpress.org/browser/open-brain/trunk/index.php#L128
• https://plugins.trac.wordpress.org/browser/open-brain/trunk/index.php#L252
• https://plugins.trac.wordpress.org/browser/open-brain/trunk/index.php#L253
• https://plugins.trac.wordpress.org/browser/open-brain/trunk/index.php#L272
• https://www.wordfence.com/threat-intel/vulnerabilities/id/3fe3fa95-cc1d-469b-8a97-37987b9ae362?source=cve