Dify Has Broken Access Control on Log Message Endpoint Allows Reading of Chats of Others

Dify is an open-source LLM app development platform. In version 1.8.1, a broken access control vulnerability on the /console/api/apps/<APP_ID>chat-messages?conversation_id=<CONVERSATION_ID>&limit=10 endpoint allows users in the same workspace to read chat messages of other users. A regular user is able to read the query data and the filename of the admins and probably other users chats, if they know the conversation_id. This impacts the confidentiality of chats. This issue has been patched in version 1.9.0.