The MainWP Child Reports plugin for WordPress is vulnerable to Missing Authorization in all versions up to and including 2.2.6. This is due to a missing capability check in the heartbeat_received() function in the Live_Update class. This makes it possible for authenticated attackers, with Subscriber-level access and above, to obtain MainWP Child Reports activity log entries (including action summaries, user information, IP addresses, and contextual data) via the WordPress Heartbeat API by sending a crafted heartbeat request with the 'wp-mainwp-stream-heartbeat' data key.