=========================================================================Ubuntu Security Notice USN-3309-1
June 05, 2017

libtasn1-6 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:

Libtasn1 could be made to crash or run programs as your login if it opened
a specially crafted file.

Software Description:
- libtasn1-6: Library to manage ASN.1 structures

Details:

Jakub Jirasek discovered that GnuTLS incorrectly handled certain
assignments files. If a user were tricked into processing a specially
crafted assignments file, a remote attacker could possibly execute arbirary
code.

Update instructions:

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

Ubuntu 17.04:
  libtasn1-6                      4.10-1ubuntu0.1

Ubuntu 16.10:
  libtasn1-6                      4.9-4ubuntu0.1

Ubuntu 16.04 LTS:
  libtasn1-6                      4.7-3ubuntu0.16.04.2

Ubuntu 14.04 LTS:
  libtasn1-6                      3.4-3ubuntu0.5

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

References:
  https://ubuntu.com/security/notices/USN-3309-1
  CVE-2017-6891

Package Information:
  https://launchpad.net/ubuntu/+source/libtasn1-6/4.10-1ubuntu0.1
  https://launchpad.net/ubuntu/+source/libtasn1-6/4.9-4ubuntu0.1
  https://launchpad.net/ubuntu/+source/libtasn1-6/4.7-3ubuntu0.16.04.2
  https://launchpad.net/ubuntu/+source/libtasn1-6/3.4-3ubuntu0.5