Whiteboards for Jira and Confluence support following access control capabilities:
Team boardanyone with access to Jira, or Confluence can access, and edit the board
Private board (Pro plan feature)board can be accessed through invite link, access must be confirmed by one of other members
Board attached to Jira issueAnyone with access to Jira issue can enter, and edit an attached board
Board embedded to Confluence pageAnyone with access to confluence page, can access the embedded board
Jira project boardProject boards are public by default. This means that everyone in your organisation can access a project whiteboard even if they don't have access to the associated Jira project. You can restrict access to individual users using the "Share" settings dialog (see screenshots below).
Confluence space boardAnyone with access to Confluence space can access the board