The Easy Appointments WordPress plugin before 3.12.28 does not correctly validate shortcode input in one of its block-rendering actions, checking only the first tag of the supplied string against an allowlist while rendering the entire string, allowing users with contributor-level access to execute arbitrary registered shortcodes.

The Easy Appointments WordPress plugin before 3.12.28 does not verify ownership or capability when returning stored customer details, allowing users with subscriber-level access to read any customer's personal information by iterating an identifier.

The Easy Appointments WordPress plugin through 4.0 does not perform capability checks in several of its appointment-management actions, relying only on a nonce that any authenticated user can obtain, allowing users with contributor-level access to read all customers' appointment details and to create, modify, and delete bookings.

Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS) vulnerability in Easy Appointments Easy Appointments easy-appointments allows Code Injection.This issue affects Easy Appointments: from n/a through <= 3.12.14.

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Nikola Loncar Easy Appointments allows Stored XSS.This issue affects Easy Appointments: from n/a through 3.10.7.