CVE-2026-9188 json
Appointment Bookings for Zoom GoogleMeet and more – Wappointment <= 2.7.6 - Unauthenticated Insecure Direct Object Reference via Predictable 'edit_key' / 'appointmentkey' Parameter
published 2026-07-02 4 mo ago modified 2026-07-02 4 mo ago also EUVD-2026-41260
- cvss
- 5.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 44%
- public exploits
- 0
- none known
Summary
The Appointment Bookings for Zoom GoogleMeet and more – Wappointment plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to and including 2.7.6 via the `appointmentkey` parameter due to the appointment `edit_key` — the sole authorization token consumed by `tryCancel()` — being generated as a predictable, unsalted MD5 hash of only `client_id` (a sequential integer), `start_at` (a publicly observable appointment timestamp), and `staff_id` (a small enumerable integer), with no secret salt or random component, and the unauthenticated cancellation and rescheduling REST endpoints performing no ownership or identity verification beyond matching this reconstructible key. This makes it possible for unauthenticated attackers to compute valid `edit_key` values for appointments belonging to other users and cancel or reschedule those appointments arbitrarily. Exploitation requires the `allow_cancellation` or `allow_rescheduling` setting to be enabled on the site, both of which are common configurations for active booking deployments; an attacker can obtain the inputs needed to reconstruct a victim's key by booking their own appointment to observe their sequential `client_id` and correlating publicly visible appointment times and enumerable staff identifiers.
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 4 mo ago
Exploit prediction
0.52% chance of exploitation in the next 30 days, higher than 44% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |
Affected products
- wappointment Appointment Bookings for Zoom GoogleMeet and more – Wappointment
Classification
- Weakness
-
- CWE-639 Authorization Bypass Through User-Controlled Key
- Technology feeds
References
- wordfence.com /threat-intel/vulnerabilities/id/07069f39-f892-4c19-8e0b-e5e17b1ffb21?source=cve
- plugins.trac.wordpress.org /browser/wappointment/tags/2.7.6/app/Services/AppointmentNew.php#L347
- plugins.trac.wordpress.org /browser/wappointment/tags/2.7.6/app/Services/AppointmentNew.php#L190
- plugins.trac.wordpress.org /browser/wappointment/tags/2.7.6/app/Models/Client.php#L39
- plugins.trac.wordpress.org /browser/wappointment/tags/2.7.6/app/Services/AppointmentNew.php#L40
- plugins.trac.wordpress.org /browser/wappointment/tags/2.7.5/app/Services/AppointmentNew.php#L347
- plugins.trac.wordpress.org /browser/wappointment/tags/2.7.5/app/Services/AppointmentNew.php#L190
- plugins.trac.wordpress.org /browser/wappointment/tags/2.7.5/app/Models/Client.php#L39
- plugins.trac.wordpress.org /browser/wappointment/tags/2.7.5/app/Services/AppointmentNew.php#L40
- plugins.trac.wordpress.org /changeset?sfp_email=&sfph_mail=&reponame=&old=3546313%40wappointment&new=3546313%40wappointment&sfp_email=&sf
Sources
- CVE List CVE-2026-9188
- NVD CVE-2026-9188
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.