gnome-screensaver 2.26.1 relies on the gnome-session D-Bus interface to determine session idle time, even when an Xfce desktop such as Xubuntu or Mythbuntu is used, which allows physically proximate attackers to access an unattended workstation on which screen locking had been intended.

gnome-screensaver before 2.28.2 allows physically proximate attackers to bypass screen locking and access an unattended workstation by moving the mouse position to an external monitor and then disconnecting that monitor.