Order Notification for Telegram <= 1.0.1 - Missing Authorization to Unauthenticated Send Telegram Test Message

The Order Notification for Telegram plugin for WordPress is vulnerable to unauthorized test message sending due to a missing capability check on the 'nktgnfw_send_test_message' function in versions up to, and including, 1.0.1. This makes it possible for unauthenticated attackers to send a test message via the Telegram Bot API to the user configured in the settings.