CVE-2026-66679

The Appointment Hour Booking – Booking Calendar plugin for WordPress is vulnerable to Stored DOM-Based Cross-Site Scripting via Booking Form Single-Line Field via Schedule Calendar List Renderer in all versions up to, and including, 1.5.97 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. Exploitation requires the 'list_readmore_numberofwords' Other Parameters setting to be configured with a positive integer value; the default value of 0 bypasses the decode-and-truncate branch entirely and is not exploitable through this sink.

The Appointment Hour Booking plugin versions up to 1.5.86 contain a Cross Site Scripting (XSS) vulnerability exploitable by contributors. A contributor can inject malicious JavaScript code.

The Appointment Hour Booking WordPress plugin before version 1.5.88 does not validate a client-supplied booking price against the server-side configured service price. Unauthenticated users can submit an arbitrary final price (including zero or negative) that is stored as the authoritative booking price, corrupting booking and payment records.