What the vulnerability does
01Description
The Booking Plugin for WordPress Appointments – Time Slot plugin for WordPress is vulnerable to unauthorized email sending in versions up to, and including, 1.4.7 due to missing validation on the tslot_appt_email AJAX action. This makes it possible for unauthenticated attackers to send appointment notification emails to arbitrary recipients with attacker-controlled text content in certain email fields, potentially enabling the site to be abused for phishing campaigns or spam distribution.
Explanation of Vulnerability in Simple Terms
02Summary
The Time Slot – Booking and Appointment System plugin contains an input validation flaw that allows attackers to modify data without authentication. An attacker can send a crafted network request to alter booking or appointment information. No user interaction is required. The vulnerability affects versions 1.4.7 and earlier.
What an attacker can do
03Attacker Capabilities
Modify booking or appointment data without logging in.
Potential impact on your site
04Site Impact
Attackers can alter appointment records, potentially disrupting bookings and customer trust.
Conditions required to exploit
05Prerequisites
Network access to the site; no authentication or user interaction required.
Key dates
06Disclosure timeline
November 19, 2025
CVE published
April 8, 2026
Record updated
