Ubuntu 16.04 LTS: USN-3029-1 Critical: NSS Denial of Service

ubuntu

July 11, 2016

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

Summary

NSS could be made to crash or run programs if it processed specially

crafted network traffic.

Software Description:

- nss: Network Security Service library

Details:

Tyson Smith and Jed Davis discovered that NSS incorrectly handled memory. A

remote attacker could use this issue to cause NSS to crash, resulting in a

denial of service, or possibly execute arbitrary code.

This update refreshes the NSS package to version 3.23 which includes

the latest CA certificate bundle. As a security improvement, this update

also modifies NSS behaviour to reject DH key sizes below 1024 bits,

preventing a possible downgrade attack.

Topics Covered

security advisory critical DoS Ubuntu NSS network issue

Update Instructions

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

Ubuntu 16.04 LTS:
  libnss3                         2:3.23-0ubuntu0.16.04.1

Ubuntu 15.10:
  libnss3                         2:3.23-0ubuntu0.15.10.1

Ubuntu 14.04 LTS:
  libnss3                         2:3.23-0ubuntu0.14.04.1

Ubuntu 12.04 LTS:
  libnss3                         2:3.23-0ubuntu0.12.04.1

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.