CVE-2026-8840

MediumCVSS 5.3/10Last modified Aug 20, 2026

Description

The Booking calendar, Appointment Booking System plugin for WordPress is vulnerable to authorization bypass in all versions up to, and including, 3.2.36. This is due to the plugin not properly verifying that a user is authorized to perform an action. This makes it possible for unauthenticated attackers to mark arbitrary reservations as paid or completed, cancel legitimate payments, auto-approve reservations, and trigger transactional booking emails by writing attacker-supplied payment status and transaction data directly into the payments table. The auto-approval of reservations is only triggered when the 'enable_psuccess_approval' site option is enabled, but payment status manipulation and email dispatch are exploitable regardless of that setting.

Metrics

CVSS 3.1 5.3/10CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Weakness enumeration

Affected software

No affected versions have been published.

Timeline

Published
Aug 15, 2026
Last modified
Aug 20, 2026
NVD status
Deferred

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CVE-2026-8840: Medium severity, CVSS 5.3 | Vulnix