CVE-2026-18315: Themetechmount Truebooker – Appointment Booking And Scheduler System

Critical severity, CVSS 9.8. EPSS: 0.6% chance of exploitation in the next 30 days.

The TrueBooker – Appointment Booking and Scheduler System plugin for WordPress is vulnerable to Authorization Bypass Through User-Controlled Key leading to Account Takeover in all versions up to, and including, 1.2.6. This is due to the admin_user_create_cus AJAX handler lacking any authentication or capability check before passing the attacker-supplied truebooker_wp_user_id parameter directly to wp_update_user. This makes it possible for unauthenticated attackers to overwrite the email address of any WordPress user — including an administrator — and then complete the standard WordPress lost-password flow to fully take over the targeted account.

Affected products

• Themetechmount Truebooker – Appointment Booking And Scheduler System: up to and including 1.2.6

Published 2026-08-19. Last modified 2026-08-21.