The Popup Box plugin for WordPress is vulnerable to Cross-Site Request Forgery in all versions up to, and including, 6.1.1. This is due to a flawed nonce implementation in the 'publish_unpublish_popupbox' function that verifies a self-created nonce rather than one submitted in the request. This makes it possible for unauthenticated attackers to change the publish status of popups via a forged request, granted they can trick a site administrator into performing an action such as clicking a link.

References 

https://plugins.trac.wordpress.org/browser/ays-popup-box/tags/6.1.0/admin/partials/ays-pb-admin-display.php#L22

https://plugins.trac.wordpress.org/browser/ays-popup-box/tags/6.1.0/includes/lists/class-ays-pb-list-table.php#L701

https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&old=3439514@ays-popup-box/tags/6.1.1/&new=3444612@ays-popup-box/tags/6.1.2/

https://www.wordfence.com/threat-intel/vulnerabilities/id/585a9eb4-f394-4cb2-9050-659171a994d9?source=cve

https://nvd.nist.gov/vuln/detail/CVE-2026-1165