# Advanced Appointment Booking & Scheduling <= 2.6 - Unauthenticated Missing Authorization to User Registration Bypass via [appointment_register_form] Shortcode

- **ID:** WPSEC-2026-2292
- **Plugin:** Advanced Appointment Booking & Scheduling (`advanced-appointment-booking-scheduling`), https://wordpress.org/plugins/advanced-appointment-booking-scheduling/
- **Affected versions:** all versions before 2.7
- **Fixed in:** 2.7 (Update to 2.7 or later.)
- **Severity:** Medium 5.3 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N)
- **Weakness:** CWE-862
- **Usage among sites WPSec scans:** plugin Low, affected versions Low (as of 2026-11-03)
- **Attack surface analysis:** https://attacksurface.wpsec.com/plugin/advanced-appointment-booking-scheduling
- **Fix released:** 2026-11-02
- **Published:** 2026-11-03
- **URL:** https://wpsec.com/vuln/WPSEC-2026-2292/

## Description

The Advanced Appointment Booking & Scheduling plugin for WordPress is vulnerable to unauthorized user registration via the [appointment_register_form] shortcode in all versions up to, and including, 2.6, due to the registration handler not checking the site's 'Anyone can register' (users_can_register) setting before calling wp_insert_user. This makes it possible for unauthenticated attackers to create and log in to new user accounts with the site's default role even when the administrator has disabled user registration. The plugin publishes a 'Register' page containing this shortcode when it is activated.

Also published later by another source as CVE-2026-81422.

## References

- https://wpsec.com/vuln/WPSEC-2026-2292/
- https://plugins.svn.wordpress.org/advanced-appointment-booking-scheduling/tags/2.7/
- https://wordpress.org/plugins/advanced-appointment-booking-scheduling/

Source: WPSec, https://wpsec.com/vuln/WPSEC-2026-2292/

License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Free to use, share and adapt, also commercially, if you credit WPSec and link to this advisory.