Microsoft Adds Bot Screening and Admin Controls to Teams Meetings

Microsoft has introduced new protections in Teams to stop unwanted third-party bots from automatically joining meetings, after warning that some service bots continued entering future meetings without users intending them to. The company said the behavior creates security and privacy risks for sensitive discussions, and its new system uses behavioral and infrastructure signals to better distinguish bots from human participants. Suspected bots are now routed to the lobby for explicit organizer approval, and organizers can see them more clearly before admitting them.

Microsoft also added a Teams admin policy that allows organizations to require approval before third-party bots can join meetings, even when regular attendees are allowed to bypass the lobby. The policy can be assigned to specific users or groups through the Teams Admin Center, while Microsoft develops a registration path for independent software vendors so approved bots can self-identify as known participants. The rollout is underway, with Microsoft planning to retire earlier CAPTCHA-based defenses and later add approved-bot allow lists, full blocking of external bots, audit logs, and reporting as part of a broader effort to harden Teams against social-engineering and impersonation abuse.