CVE-2026-89063 Details

A vulnerability allowing insecure direct object reference has been identified in the Bookly WordPress plugin, specifically in the Online Scheduling and Appointment Booking System component, in all versions through 28.1. The issue arises from the 'conversation_id' parameter, which lacks proper validation, allowing unauthenticated attackers to access sensitive information. Exploitation of this vulnerability enables attackers to read private AI booking conversation transcripts of customers, including names, email addresses, phone numbers, and appointment details. Additionally, attackers can inject arbitrary messages into any victim's conversation, which are then relayed to the Cloud AI worker along with the full conversation history. This vulnerability is particularly concerning because AI conversations are stored without any identifiers, and conversation IDs can be easily enumerated by incrementing the 'conversation_id' parameter.

Users are advised to update the Bookly WordPress plugin to version 28.2 or later, where this vulnerability has been patched.