Microsoft Teams: CVI support for Townhall and Webinar presenters

🚨 The Signal: Microsoft Teams now supports Cloud Video Interoperability (CVI) for Town Hall and Webinar presenters, allowing external VTC devices to join. This expands collaboration but introduces new potential attack surfaces for event access.

The Impact

Security teams and event organizers are affected by new external access vectors, increasing the risk of unauthorized meeting access or data exfiltration.

• Security Teams: Increased attack surface from external VTC devices.
• Event Organizers: Need to validate CVI presenter identities and access.
• Network Administrators: Review firewall rules for CVI traffic.
• Incident Response: New potential vectors for unauthorized access.

The Action

1. Review existing Teams meeting policies for CVI integration.
2. Implement Conditional Access policies to restrict CVI access to trusted networks/devices.
3. Educate event organizers on secure CVI presenter invitation practices.
4. Monitor Teams audit logs for unusual CVI join activities.

Domain: Teams · Impact: high · Workload: Teams