@TheMedievalMan1 @Ubisoft_UK Hey, thanks for reporting this. Could you tell us which playform this happened on, and would you be able to share a video of the issue with us?
To fix an exploit where players could join lobbies uninvited, we have released a hotfix that will require PC players to have at least one friend already in the squad.
Thank you for all your patience!
To clarify, now players can only join games in which they have a friend already in that squad (whether it be the squad host, or someone else already in that party).
Players can no longer use an exploit to force themselves into squads with other players.