CVE-2026-18496 [MEDIUM] – The Booking Calendar plugin for WordPress is vulnerable to Sensitive Information Exposure

The Booking Calendar plugin for WordPress is vulnerable to Sensitive Information Exposure in all versions up to, and including, 11.4.3 via the wpbc_is_show_popover_in_flex_timeline() function. This makes it possible for unauthenticated attackers to extract sensitive data including names, email addresses, and phone numbers of customers who have made bookings.