=========================================================================Ubuntu Security Notice USN-3786-1
October 08, 2018

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

- Ubuntu 16.04 LTS
- Ubuntu 14.04 LTS

Summary:

Several security issues were fixed in libxkbcommon.

Software Description:
- libxkbcommon: library interface to the XKB compiler - development
files

Details:

It was discovered that libxkbcommon incorrectly handled certain files.
An attacker could possibly use this issue to cause a denial of service.
(CVE-2018-15853, CVE-2018-15854, CVE-2018-15855, CVE-2018-15856,
CVE-2018-15857, CVE-2018-15858, CVE-2018-15859, CVE-2018-15861,
CVE-2018-15862, CVE-2018-15863, CVE-2018-15864)

Update instructions:

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

Ubuntu 16.04 LTS:
  libxkbcommon-x11-0              0.5.0-1ubuntu2.1
  libxkbcommon0                   0.5.0-1ubuntu2.1

Ubuntu 14.04 LTS:
  libxkbcommon-x11-0              0.4.1-0ubuntu1.1
  libxkbcommon0                   0.4.1-0ubuntu1.1

In general, a standard system update will make all the necessary
changes.

References:
  https://ubuntu.com/security/notices/USN-3786-1
  CVE-2018-15853, CVE-2018-15854, CVE-2018-15855, CVE-2018-15856,
  CVE-2018-15857, CVE-2018-15858, CVE-2018-15859, CVE-2018-15861,
  CVE-2018-15862, CVE-2018-15863, CVE-2018-15864

Package Information:
  https://launchpad.net/ubuntu/+source/libxkbcommon/0.5.0-1ubuntu2.1
  https://launchpad.net/ubuntu/+source/libxkbcommon/0.4.1-0ubuntu1.1