CVE-2026-89063

high

Description

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.

References

https://www.wordfence.com/threat-intel/vulnerabilities/id/b6af015f-f954-4afb-9d65-56176f73672f?source=cve

https://plugins.trac.wordpress.org/browser/bookly-responsive-appointment-booking-tool/tags/28.1/lib/base/Component.php#L67

https://plugins.trac.wordpress.org/browser/bookly-responsive-appointment-booking-tool/tags/28.1/frontend/modules/ai/Ajax.php#L60

https://plugins.trac.wordpress.org/browser/bookly-responsive-appointment-booking-tool/tags/28.1/frontend/modules/ai/Ajax.php#L38

https://plugins.trac.wordpress.org/browser/bookly-responsive-appointment-booking-tool/tags/28.1/frontend/modules/ai/Ajax.php#L215

https://plugins.trac.wordpress.org/browser/bookly-responsive-appointment-booking-tool/tags/28.1/frontend/modules/ai/Ajax.php#L212

Details

Source: Mitre, NVD

Published: 2026-09-16

Updated: 2026-09-17

Risk Information

CVSS v2

Base Score: 7.8

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:N/A:N

Severity: High

CVSS v3

Base Score: 7.5

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Severity: High

EPSS

EPSS: 0.00392