===========================================================================
Ubuntu Security Notice USN-3270-1
April 27, 2017

nss vulnerabilities
===========================================================================

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:

Several security issues were fixed in NSS.

Software Description:
- nss: Network Security Service library

Details:

Karthik Bhargavan and Gaetan Leurent discovered that the DES and Triple DES
ciphers were vulnerable to birthday attacks. A remote attacker could
possibly use this flaw to obtain clear text data from long encrypted
sessions. This update causes NSS to limit use of the same symmetric key.
(CVE-2016-2183)

It was discovered that NSS incorrectly handled Base64 decoding. A remote
attacker could use this flaw to cause NSS to crash, resulting in a denial
of service, or possibly execute arbitrary code. (CVE-2017-5461)

This update refreshes the NSS package to version 3.28.4 which includes
the latest CA certificate bundle.

Update instructions:

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

Ubuntu 17.04:
  libnss3                         2:3.28.4-0ubuntu0.17.04.1

Ubuntu 16.10:
  libnss3                         2:3.28.4-0ubuntu0.16.10.1

Ubuntu 16.04 LTS:
  libnss3                         2:3.28.4-0ubuntu0.16.04.1

Ubuntu 14.04 LTS:
  libnss3                         2:3.28.4-0ubuntu0.14.04.1

This update uses a new upstream release, which includes additional bug
fixes. After a standard system update you need to restart any applications
that use NSS, such as Evolution and Chromium, to make all the necessary
changes.

References:
  http://www.ubuntu.com/usn/usn-3270-1
  CVE-2016-2183, CVE-2017-5461

Package Information:
  https://launchpad.net/ubuntu/+source/nss/2:3.28.4-0ubuntu0.17.04.1
  https://launchpad.net/ubuntu/+source/nss/2:3.28.4-0ubuntu0.16.10.1
  https://launchpad.net/ubuntu/+source/nss/2:3.28.4-0ubuntu0.16.04.1
  https://launchpad.net/ubuntu/+source/nss/2:3.28.4-0ubuntu0.14.04.1