USN-3270-1: NSS vulnerabilities

Ubuntu Security Notice USN-3270-1

27th April, 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


Several security issues were fixed in NSS.

Software description

  • nss - Network Security Service library


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.

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 version:

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

To update your system, please follow these instructions:

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


CVE-2016-2183, CVE-2017-5461