If easily accessible control elements of BACS are inadequately secured, they can be used to attack such systems. Examples of these elements include wall-mounted control elements or control elements of gatekeepers that can be used to open doors or gates remotely.

If such control elements are inadequately protected, (e.g. due to a lack of authentication), this can enable unauthorised access.

Inadequately protected connections of control elements such as LAN or USB interfaces can also open the door to unauthorised users.