Preventing & Addressing Videoconference Bombing in Microsoft Teams

Videoconference Bombing — the screen sharing of inappropriate content by an online intruder — is a rising cyber threat. Find out how to prevent and address Videoconference Bombing when using Microsoft Teams. 

Zoom Videoconferencing

IMPORTANT: IT Services and the Center for Cyber Security Awareness and Cyber Defense encourage students, faculty and staff to use Microsoft Teams, which is supported by the university and the preferred videoconferencing tool. Zoom videoconferencing is not supported at Marquette University. For information about Zoom and Videoconference Bombing, also known as ZoomBombing, see these instructions from Zoom.

 

Having trouble with Videoconferencing Bombing right now?

Jump to "Address Now"


How to prevent Videoconference Bombing

Here are several ways to prevent Videoconference Bombing from disrupting your online class session or meeting.

  • Selectively share the "Join Meeting Link"

    Teams sessions and meetings are open to anyone with the "Join Microsoft Teams Meeting" link. Do not share the join link widely. Only give out the join link to those who should attend.

  • Encourage participants to join with their Marquette login

    Having participants join with their Marquette login means there will be fewer anonymous guests for you to monitor. Participants who use the Marquette login show up by name in Teams — which also can discourage disruptions.

  • Set the lobby to screen guest access

    Consider screening guests who have the join link by switching off lobby bypass. The lobby is a waiting area for guests who are not logged in with Teams software. The default setting allows everyone to bypass the lobby as soon as the first logged-in instructor, student or staff member joins the session via Teams software. With lobby bypass on, any guests immediately join the meeting. That's how a Videoconference Bombing "guest" intruder — who has the join link — can enter your session. Alternatively, you can switch off lobby bypass and selectively admit guests.

    Click or tap here for steps to switch off lobby bypass for a session/meeting

    Remember: If you switch off lobby bypass, Teams will prompt you when guests arrive in the lobby. Guests can include students or participants calling in by phone. (Of course, phone callers cannot screen share. But if the caller is an intruder, the bad actor may be verbally abusive.) You'll need to admit any guests during your session/meeting.

    1. Access the meeting options link. Only the person who created the Teams session or meeting is authorized to change the meeting options.
    2. Otherwise, go to your calendar in Outlook on the Web Calendar, Microsoft Outlook calendar or Microsoft Teams calendar.
    3. Double-click to fully open the specific calendar event item for your online class session or meeting. If you single-click, a pop-up preview of the event may appear, and the preview may not show you what you need.
    4. Online class session/meeting details will appear, as pictured below. Click or tap Meeting options.

      Meeting Options
    5. A web page appears with meeting options. For "Who can bypass the lobby?" select "People in my organization." Only logged-in Marquette students, instructors and staff members can bypass the lobby. Guests cannot.

      Lobby bypass

      Alternatively, for "Who can bypass the lobby?" you could select "Only me" if you wanted to screen all participants before they join the meeting.

    6. Click or tap the Save button
  • Check the participants list during the session

    After joining the session in Teams, review the names on the participants list for strangers.

    Click or tap here for steps to check the participants list in Teams

    1. On the Teams controls, click or tap the participants icon.

      Click or tap participants icon

    2. The participant list appears. If feasible, confirm you recognize all people in the session. Note that some people may join by phone and will show by their phone number. The image below shows the default setup. By default, all the participants you see on the "In this meeting" list are Presenters — including the Intruder "guest." If you've given any participants the Attendee role, you'll see them listed separately.  

      People list for participants in Teams
    3. If you discover someone who should not be in the session, follow the "Address Videoconference Bombing Now" steps to oust the intruder before trouble occurs.
  • Apply the attendee role and selectively promote presenters

    By default, everyone who joins the session has the presenter role. Presenters can do a lot: share content, mute or remove participants, admit guests from the lobby, start or stop recording and more. Consider setting up presenter and attendee roles for participants. Attendees are limited to speaking if unmuted, showing their webcam video and using the group Meeting Chat. Also, you can promote attendees to the presenter role when needed during the meeting.

    Learn more about Teams meeting roles of Organizer, Presenter and Attendee.

    Click or tap here for steps to set up the attendee role via Meeting options link

    Set up who can present, which also assigns the attendee role

    1. Access the meeting options link. Only the person who created the Teams session or meeting is authorized to change the meeting options.
    2. Otherwise, go to your calendar in Outlook on the Web Calendar, Microsoft Outlook calendar or Microsoft Teams calendar.
    3. Double-click to fully open the specific calendar event item for your online class session or meeting. If you single-click, a pop-up preview of the event may appear, and the preview may not show you what you need.
    4. Online class session/meeting details will appear, as pictured below. Click or tap Meeting options.

      Meeting Options
    5. A web page appears with meeting options. For "Who can present?" make sure the selected option is something other than "Everyone" or "People in my organization and trusted organizations."
      • Only me means the creator of the meeting/session is the sole presenter. Everyone else will join with the attendee role.
      • People in my organization means that any logged-in Marquette student, instructor or staff member is a presenter. Guests join with the attendee role.
      • Specific people applies if you have already specified invitees for the session. You are presented a drop-down menu of invitees to select who will have the presenter role upon joining.

        Select who can present
    6. If you made changes, click or tap the Save button.
     

    Click or tap here for steps to promote an attendee to a presenter

    Promote an attendee to a presenter during the session

    1. On the Teams controls, click or tap the participants icon.

      Click or tap participants icon

    2. The participants list appears. Hover over the name of an attendee who you want to make a presenter. The three-dots icon appears. Select the three-dots icon then choose Make a presenter.

      Select make a presenter

    3. Teams prompts you to confirm you want to change who can present. Click or tap the Change button.

      Change who can present

    4. Teams notifies the person changed to presenter of the new role.



Address Videoconference Bombing now

Is your session being disrupted by Videoconference Bombing right now? Take these steps to thwart the intruder.

A. Make the intruder an attendee then remove the intruder.

  1. On the Teams controls, click or tap the participants icon.

    Click or tap participants icon

  2. The participants list appears. The trouble is that the intruder joined with the presenter role by default. Hover over the name of the intruder. The three-dots icon appears. Select the three-dots icon then choose Make an attendee.

    Select make an attendee

  3. Teams prompts you to confirm you want to change who can present. Click or tap the Change button. The intruder becomes an attendee.
  4. Hover over the name of the intruder again. The three-dots icon appears. Select the three-dots icon then choose Remove from meeting. 

    Remove participant

    Removing the intruder ends the screen sharing of inappropriate content. If the intruder rejoins the meeting, the intruder's role is an attendee and cannot screen share.

    Next, let's block the intruder from rejoining the session.

B. Fix meeting options: Turn lobby bypass off and set presenter to "only me."

  1. To keep the intruder from rejoining the session, access the meeting options link. Only the person who created the Teams session or meeting is authorized to change the meeting options.
  2. Otherwise, from the Microsoft Teams controls, click or tap the three-dots icon. From the menu, select Show meeting details.

    Select show meeting details

  3. Online class session/meeting details will appear, as pictured below. Click or tap Meeting options.

    Meeting Options

  4. A web page appears with meeting options. For "Who can bypass the lobby?" select "People in my organization." For "Who can present?" select "Only me." The "only me" setting makes you the sole presenter and puts all other participants in the attendee role. As attendees, your students and participants cannot inadvertently re-admit the intruder from the lobby. Click or tap the Save button.

    Fix meeting options

  5. If the intruder rejoined before you could switch off the lobby bypass, remove the participant again. The intruder may attempt to rejoin the session — but will be held in the lobby this time, unable to join the meeting.

Report Videoconference Bombing

If you encounter Videoconference Bombing in a Teams online class session or meeting, report the incident to the IT Services Help Desk.