Cloud-based software always presents some risks, and Microsoft 365 is designed to be collaboration software with data stored in the cloud. While the risk is minimal, only the person or organization hosting a meeting or conference bears any real risk. Individuals using their own computers or other devices to participate in the event should not be concerned. If you use split-tunneling to bypass your VPN to attend a Microsoft Teams event, Teams encrypts the traffic and uses other security measures to give you peace of mind. Security experts believe Teams is sufficiently secure.