Salon Booking System < 10.31.9 - Administrator Account Creation via CSRF

The Salon Booking System WordPress plugin before 10.31.9 does not correctly verify the authenticity of REST API requests and discards WordPress core's nonce check for cookie-authenticated sessions across the whole REST API, allowing unauthenticated attackers who trick a logged-in administrator into clicking a crafted link to forge requests in that administrator's browser, up to creating a new administrator account.