==========================================================================
Ubuntu Security Notice USN-3353-1
July 14, 2017

heimdal vulnerability
==========================================================================

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

- Ubuntu 17.04
- Ubuntu 16.10
- Ubuntu 16.04 LTS
- Ubuntu 14.04 LTS

Summary:

Heimdal could allow unintended access to network services.

Software Description:
- heimdal: Heimdal Kerberos Network Authentication Protocol

Details:

Jeffrey Altman, Viktor Dukhovni, and Nicolas Williams discovered
that Heimdal clients incorrectly trusted unauthenticated portions
of Kerberos tickets. A remote attacker could use this to impersonate
trusted network services or perform other attacks.

Update instructions:

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

Ubuntu 17.04:
  libkrb5-26-heimdal              7.1.0+dfsg-9ubuntu1.1

Ubuntu 16.10:
  libkrb5-26-heimdal              1.7~git20150920+dfsg-4ubuntu1.16.10.1

Ubuntu 16.04 LTS:
  libkrb5-26-heimdal              1.7~git20150920+dfsg-4ubuntu1.16.04.1

Ubuntu 14.04 LTS:
  libkrb5-26-heimdal              1.6~git20131207+dfsg-1ubuntu1.2

After a standard system update you need to restart any applications
using Heimdal libraries to make all the necessary changes.

References:
  https://www.ubuntu.com/usn/usn-3353-1
  CVE-2017-11103

Package Information:
  https://launchpad.net/ubuntu/+source/heimdal/7.1.0+dfsg-9ubuntu1.1
  https://launchpad.net/ubuntu/+source/heimdal/1.7~git20150920+dfsg-4ubuntu1.16.10.1
  https://launchpad.net/ubuntu/+source/heimdal/1.7~git20150920+dfsg-4ubuntu1.16.04.1
  https://launchpad.net/ubuntu/+source/heimdal/1.6~git20131207+dfsg-1ubuntu1.2