Easy PayPal Events & Tickets < 1.4 Authentication Bypass via QR Code Scanning

Easy PayPal Events & Tickets plugin for WordPress before version 1.4 contains a hardcoded authentication bypass vulnerability in the QR code scanning functionality that allows unauthenticated remote attackers to bypass hash verification by supplying 'test' as the hash parameter. Attackers can access the vulnerable endpoint via the add_wpeevent_button_qr action to retrieve sensitive order details including PayPal transaction IDs, customer email addresses, purchase amounts, and ticket information for any order with a known or guessed post ID.