USN-3431-1: NSS vulnerability

2 October 2017

nss vulnerability

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

  • Ubuntu 17.04
  • Ubuntu 16.04 LTS
  • Ubuntu 14.04 LTS


NSS could be made to crash or run programs if it received specially crafted network traffic.

Software Description

  • nss - Network Security Service library


Martin Thomson discovered that NSS incorrectly generated handshake hashes. A remote attacker could use this issue to cause NSS to crash, resulting in a denial of service, or possibly execute arbitrary code.

Update instructions

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

Ubuntu 17.04
libnss3 - 2:3.28.4-0ubuntu0.17.04.3
Ubuntu 16.04 LTS
libnss3 - 2:3.28.4-0ubuntu0.16.04.3
Ubuntu 14.04 LTS
libnss3 - 2:3.28.4-0ubuntu0.14.04.3

To update your system, please follow these instructions:

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.