unity vulnerabilities

USN-2184-1 fixed lock screen vulnerabilities in Unity. Further testing has
uncovered more issues which have been fixed in this update. This update
also fixes a regression with the shutdown dialogue.

We apologize for the inconvenience.

Original advisory details:

Frédéric Bardy discovered that Unity incorrectly filtered keyboard
shortcuts when the screen was locked. A local attacker could possibly use
this issue to run commands, and unlock the current session.

Giovanni Mellini discovered that Unity could display the Dash in certain
conditions when the screen was locked. A local attacker could possibly use
this issue to run commands, and unlock the current session.