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CVE-2026-86839: CWE-639 Authorization Bypass Through User-Controlled Key in Online Scheduling and Appointment Booking System

0
Low
VulnerabilityCVE-2026-86839cvecve-2026-86839cwe-639
Published: 09/27/2026 (09/27/2026, 06:00:20 UTC)
Source: CVE Database V5
Product: Online Scheduling and Appointment Booking System

Description

The Online Scheduling and Appointment Booking System WordPress plugin before 28.3 does not verify that appointment and payment records requested through its staff-role AJAX actions belong to the requesting staff member, allowing authenticated attackers with a staff-level account to view, modify and delete other staff members' appointments and payments, including the associated customer's personal information.

CVSS v3.1

Score 3.8low

Attack Vector
Network
Attack Complexity
Low
Privileges Required
High
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
Low
Availability
None
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:N

Affected software

Online Scheduling and Appointment Booking System

Affected versions
>=0 <28.3

AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 09/27/2026, 06:18:23 UTC

Technical Analysis

CVE-2026-86839 is an authorization bypass vulnerability in the Online Scheduling and Appointment Booking System WordPress plugin versions prior to 28.3. The plugin fails to verify that appointment and payment records accessed via staff-role AJAX actions belong to the requesting staff member. This flaw allows authenticated staff-level users to view, modify, and delete other staff members' appointments and payments, exposing sensitive customer data.

Potential Impact

Authenticated staff-level attackers can access and manipulate appointment and payment data of other staff members, including sensitive customer personal information. This could lead to unauthorized data disclosure, data tampering, and potential privacy violations.

Mitigation Recommendations

Upgrade the Online Scheduling and Appointment Booking System WordPress plugin to version 28.3 or later where this vulnerability is fixed. No other mitigation guidance is provided; applying the official update is the recommended remediation.

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Technical Details

Data Version
5.2
Assigner Short Name
WPScan
Date Reserved
2026-09-08T14:43:22.104Z
State
PUBLISHED

Threat ID: 6ab8b2d5f7a7c54106aa92d7

Added to database: 09/27/2026, 06:08:21 UTC

Last enriched: 09/27/2026, 06:18:23 UTC

Last updated: 09/28/2026, 01:57:30 UTC

Views: 17

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