FreeScout: Missing Authorization and Exposure of Sensitive Information to an Unauthorized Actor and Authorization Bypass Through User-Controlled Key

FreeScout is a self-hosted help desk and shared mailbox. Prior to 1.8.226, RealtimeConvNewThread checks only general mailbox access and does not apply the conversation-level restriction for users configured to see only assigned conversations. A restricted authenticated user can subscribe to predictable conv.<conversation_id> Polycast channels for other conversations in the same mailbox. New event payloads can expose complete replies, internal notes, recipient addresses, conversation state, assignee data, attachment names, and attachment URLs containing valid download tokens. This issue is fixed in version 1.8.226.