CVE-2026-89063
HighCVSS 7.5Summary
The Online Scheduling and Appointment Booking System – Bookly plugin for WordPress in all versions up to and including 28.1 is vulnerable to Insecure Direct Object Reference via the 'conversation_id' parameter due to missing validation on a user-controlled key. This allows unauthenticated attackers to read the full AI booking conversation transcript of any customer — leaking names, email addresses, phone numbers, and appointment details — and inject arbitrary messages into any victim conversation. Because AI conversations are stored with no owner, user, or session identifier and conversation IDs are sequential integers, an unauthenticated attacker can enumerate all customer conversations by incrementing the conversation_id parameter.
Risk Assessment
An attacker can mass-leak customers' personal data (names, emails, phones, appointment details) and inject fake messages into conversations. This is a serious privacy breach that may lead to fraud and GDPR violations.
Recommendation
Update the Bookly plugin to a version later than 28.1 or disable it if no update is available. Immediately assess the scope of the data leak and consider reporting the breach in accordance with GDPR.
Other vulnerabilities in Bookly
See all- CVE-2026-2520Medium
The Bookly plugin for WordPress is vulnerable to unauthorized data modification due to a missing capability check in the 'updateAddon' function in all versions up to and including 27.2. This allows authenticated attackers with Subscriber-level access and above to update any plugin with a main file of 'main.php' to its latest version.
- CVE-2026-61944High
The Bookly plugin up to version 27.7 contains an unauthenticated Cross Site Scripting (XSS) vulnerability. An unauthenticated attacker can inject a malicious script that executes in the victim's browser.
- CVE-2026-61949Critical
The Bookly plugin versions up to 27.7 are vulnerable to unauthenticated SQL injection.
- CVE-2026-13424High
The Bookly plugin for WordPress up to version 27.7 is vulnerable to Stored Cross-Site Scripting via the bookly_speed_up_update_addons AJAX action. Unauthenticated attackers can inject arbitrary scripts that execute when an administrator views the Diagnostics → Logs page.
- CVE-2026-12905Medium
The Bookly plugin for WordPress up to version 27.7 is vulnerable to Insecure Direct Object Reference in the appointment() method of the Mobile Staff Cabinet API. The handler loads an Appointment by the attacker-supplied id without verifying that the appointment's staff_id matches the authenticated staff member. Authenticated attackers with staff-level mobile cabinet access can read appointment details of other staff members, including internal notes and customer data, by enumerating sequential IDs.
- CVE-2026-42667High
In Bookly versions up to 27.4, there is a vulnerability allowing unauthorized access to sensitive data.
- CVE-2026-5513High
The Bookly plugin for WordPress up to version 27.2 contains a Stored XSS vulnerability in the 'bookly-customer-full-name' cookie. An unauthenticated attacker can inject scripts that execute when an administrator visits an infected page. Requires the 'Remember personal information in cookies' setting to be enabled (disabled by default).
Original NVD description (English source)
The Online Scheduling and Appointment Booking System – Bookly plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 28.1 via the 'conversation_id' parameter due to missing validation on a user controlled key. This makes it possible for unauthenticated attackers to read the full AI booking conversation transcript of any customer — leaking names, email addresses, phone numbers, and appointment details echoed by the assistant — and inject arbitrary messages into any victim conversation that are subsequently replayed to the Cloud AI worker along with the full private history. Because AI conversations are stored with no owner, user, or session identifier and conversation IDs are sequential integers, an unauthenticated attacker can enumerate all customer conversations simply by incrementing the conversation_id parameter.