Unity before 7.2.1, as used in Ubuntu 14.04, does not properly restrict access to the Dash when the lock screen is active, which allows phy…

Unity before 7.2.1, as used in Ubuntu 14.04, does not properly restrict access to the Dash when the lock screen is active, which allows physically proximate attackers to bypass the lock screen and execute arbitrary commands, as demonstrated by pressing the SUPER key before the screen auto-locks.