# Fluent Booking – The Ultimate Appointments Scheduling, Events Booking, Events Calendar Solution <= 2.5.0 - Authenticated (Subscriber+) Insecure Direct Object Reference to Guest Bookings via My Bookings List

- **ID:** WPSEC-2026-2590
- **Plugin:** Fluent Booking – The Ultimate Appointments Scheduling, Events Booking, Events Calendar Solution (`fluent-booking`), https://wordpress.org/plugins/fluent-booking/
- **Affected versions:** all versions before 2.6.0
- **Fixed in:** 2.6.0 (Update to 2.6.0 or later.)
- **Severity:** Medium 5.4 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N)
- **Weakness:** CWE-639
- **Usage among sites WPSec scans:** plugin Low, affected versions Low (as of 2026-11-05)
- **Attack surface analysis:** https://attacksurface.wpsec.com/plugin/fluent-booking
- **Fix released:** 2026-11-04
- **Published:** 2026-11-05
- **URL:** https://wpsec.com/vuln/WPSEC-2026-2590/

## Description

The Fluent Booking plugin for WordPress is vulnerable to Insecure Direct Object Reference via the 'My Bookings' list ([fluent_booking_lists] shortcode and the front-end bookings endpoint) in all versions up to, and including, 2.5.0. This is due to the list selecting bookings by the logged-in user's email address alone, with no check that the booking belongs to that account, while WordPress lets a user change their account email through the REST API without verifying the inbox. This makes it possible for authenticated attackers, with subscriber-level access and above, to set their account email to a guest's address and then view that guest's bookings. The list also links to each booking's management page, so the attacker can cancel or reschedule them.

## References

- https://wpsec.com/vuln/WPSEC-2026-2590/
- https://plugins.svn.wordpress.org/fluent-booking/tags/2.6.0/
- https://wordpress.org/plugins/fluent-booking/

Source: WPSec, https://wpsec.com/vuln/WPSEC-2026-2590/

License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Free to use, share and adapt, also commercially, if you credit WPSec and link to this advisory.