---
id: CVE-2026-91847
title: >-
  The Online Scheduling and Appointment Booking System  WordPress plugin before
  28.2 does not verify that the requester owns the AI booking-assistant
  conversation named in its unauthenticated conversation actions, allowing any
  unauthentica…
summary: >-
  The Online Scheduling and Appointment Booking System  WordPress plugin before
  28.2 does not verify that the requester owns the AI booking-assistant
  conversation named in its unauthenticated conversation actions, allowing any
  unauthentica…
severity: medium
cvss: 4.8
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N'
cwe:
  - CWE-639
product: Online Scheduling and Appointment Booking System
affected:
  - online_scheduling_and_appointment_booking_system >= 28.1 < 28.2
published: '2026-09-19'
updated: '2026-09-21'
sourceUpdated: '2026-09-21T13:34:57.127'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-91847'
references:
  - url: 'https://wpscan.com/vulnerability/9eef3086-3a67-4ee2-bd78-e346e7b05d62/'
    label: contact@wpscan.com
tags:
  - nvd
  - cve.org
epss: 0.00217
epssPercentile: 0.10779
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-19T13:11:43.956388Z'
ingestedAt: '2026-09-19T06:59:13.112Z'
---

## Overview

The Online Scheduling and Appointment Booking System  WordPress plugin before 28.2 does not verify that the requester owns the AI booking-assistant conversation named in its unauthenticated conversation actions, allowing any unauthenticated visitor to read another visitor's assistant messages and to inject messages into their in-progress conversation.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.