USN-4134-2: IBus regression

23 September 2019

ibus regression

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

  • Ubuntu 19.04
  • Ubuntu 18.04 LTS
  • Ubuntu 16.04 LTS


USN 4134-1 introduced a regression in IBus.

Software Description

  • ibus - Intelligent Input Bus - core


USN-4134-1 fixed a vulnerability in IBus. The security fix introduced a regression when being used with Qt applications. This update reverts the security fix pending further investigation.

Original advisory details:

Simon McVittie discovered that IBus did not enforce appropriate access controls on its private D-Bus socket. A local unprivileged user who discovers the IBus socket address of another user could exploit this to capture the key strokes of the other user.

Update instructions

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

Ubuntu 19.04
ibus - 1.5.19-1ubuntu2.2
Ubuntu 18.04 LTS
ibus - 1.5.17-3ubuntu5.2
Ubuntu 16.04 LTS
ibus - 1.5.11-1ubuntu2.3

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.