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CVE-2026-86841

Medium

Description

The Online Scheduling and Appointment Booking System WordPress plugin before 28.3 does not prevent deserialization of untrusted input and does not correctly restrict a privileged maintenance feature to administrators, allowing users granted a custom booking-management capability, which an administrator must explicitly assign, to inject arbitrary PHP objects, overwrite privileged site options, and read stored integration secrets.

SeverityMedium
CVSS4.7
Exploit probability—
ProductOnline Scheduling and Appointment Booking System
PublishedSep 27, 2026
First seenSep 27, 2026
Weakness typeCWE-502Deserialization of untrusted data

How to fix

Update
  • Online Scheduling and Appointment Booking System28.3 or later

Affected products

ProductAffected versionsFixed in
Online Scheduling and Appointment Booking System23.2 ≤ v < 28.328.3

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