Stop Anonymous Users Sending Chat Messages
Microsoft rolled out a new feature – check Microsoft 365 Roadmap item 392295 – that warns admins about the risks associated with allowing unauthenticated or anonymous users to send chat messages within a team meeting. As mentioned, the alert notes that some institutions like finance consider chat messages as forms of data exfiltration. Please keep in mind that anonymous and users without Microsoft authentication can still join the meeting AND read the chat. If you are really concerned that confidential information could leak and create data extrusion, then it is recommended to prevent anonymous and non-authenticated users from joining the meeting.
Microsoft (and especially Stephen Rose, Principal Product Manager) asked me to join their video series “Inside Microsoft Teams” to talk about these new Admin capabilities. Find my video and blogpost here