USN-3861-1: PolicyKit vulnerability

16 January 2019

policykit-1 vulnerability

A security issue affects these releases of Ubuntu and its derivatives:

  • Ubuntu 18.10
  • Ubuntu 18.04 LTS
  • Ubuntu 16.04 LTS
  • Ubuntu 14.04 LTS


PolicyKit could allow unintended access.

Software Description

  • policykit-1 - framework for managing administrative policies and privileges


It was discovered that PolicyKit incorrectly handled certain large user UIDs. A local attacker with a large UID could possibly use this issue to perform privileged actions.

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 18.10
libpolkit-backend-1-0 - 0.105-21ubuntu0.3
policykit-1 - 0.105-21ubuntu0.3
Ubuntu 18.04 LTS
libpolkit-backend-1-0 - 0.105-20ubuntu0.18.04.4
policykit-1 - 0.105-20ubuntu0.18.04.4
Ubuntu 16.04 LTS
libpolkit-backend-1-0 - 0.105-14.1ubuntu0.4
policykit-1 - 0.105-14.1ubuntu0.4
Ubuntu 14.04 LTS
libpolkit-backend-1-0 - 0.105-4ubuntu3.14.04.5
policykit-1 - 0.105-4ubuntu3.14.04.5

To update your system, please follow these instructions:

After a standard system update you need to reboot your computer to make all the necessary changes.