Appointment Booking Plugin <= 5.7.2 - Unauthenticated Authentication Bypass to Customer Account Takeover via Insufficient Verification in create_wp_user_for_customer() username_exists Fallback

Summary

The Appointment Booking Plugin – LatePoint | Calendar & Scheduling for WordPress plugin for WordPress is vulnerable to Authentication Bypass in versions up to, and including, 5.7.2 via the OsCustomerHelper::create_wp_user_for_customer() helper reached from the public process_step_customer() booking step. When the 'Use WordPress users as customers' option is enabled, the helper falls back from email_exists() to username_exists( $customer->email ), which matches any WordPress user whose user_login equals the victim customer's email even when that user's user_email is completely different, and links that WordPress user's ID into the victim's LatePoint customer row (only privileged roles are excluded; Subscriber is allowed). This makes it possible for authenticated attackers, with Subscriber-level access and above, to take over another customer's LatePoint account — accessing their bookings, service, agent, and calendar data, and having the victim customer's email overwritten with the attacker's on next login — by holding a Subscriber account whose user_login equals the victim's email and submitting an unauthenticated public booking step registration request.

Timeline

1. Oct 14, 2026, 7:43 AM UTCCVE published
2. Oct 14, 2026, 5:40 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: no · Technical impact: total

3. Oct 14, 2026, 5:41 PM UTCRecord last updated

Affected versions

• latepoint Appointment Booking Plugin – LatePoint | Calendar & Scheduling for WordPress

  through 5.7.2

References 7