=========================================================================Ubuntu Security Notice USN-2865-1
January 08, 2016

gnutls26, gnutls28 vulnerability
=========================================================================
A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 15.04
- Ubuntu 14.04 LTS
- Ubuntu 12.04 LTS

Summary:

GnuTLS could be made to expose sensitive information over the network.

Software Description:
- gnutls28: GNU TLS library
- gnutls26: GNU TLS library

Details:

Karthikeyan Bhargavan and Gaetan Leurent discovered that GnuTLS incorrectly
allowed MD5 to be used for TLS 1.2 connections. If a remote attacker were
able to perform a man-in-the-middle attack, this flaw could be exploited to
view sensitive information.

Update instructions:

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

Ubuntu 15.04:
  libgnutls-deb0-28               3.3.8-3ubuntu3.2
  libgnutls-openssl27             3.3.8-3ubuntu3.2
  libgnutlsxx28                   3.3.8-3ubuntu3.2

Ubuntu 14.04 LTS:
  libgnutls-openssl27             2.12.23-12ubuntu2.4
  libgnutls26                     2.12.23-12ubuntu2.4
  libgnutlsxx27                   2.12.23-12ubuntu2.4

Ubuntu 12.04 LTS:
  libgnutls-openssl27             2.12.14-5ubuntu3.11
  libgnutls26                     2.12.14-5ubuntu3.11
  libgnutlsxx27                   2.12.14-5ubuntu3.11

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

References:
  https://ubuntu.com/security/notices/USN-2865-1
  CVE-2015-7575

Package Information:
  https://launchpad.net/ubuntu/+source/gnutls28/3.3.8-3ubuntu3.2
  https://launchpad.net/ubuntu/+source/gnutls26/2.12.23-12ubuntu2.4
  https://launchpad.net/ubuntu/+source/gnutls26/2.12.14-5ubuntu3.11