USN-1007-1: NSS vulnerabilities

20 October 2010

nss vulnerabilities

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

  • Ubuntu 10.10
  • Ubuntu 10.04 LTS
  • Ubuntu 9.10
  • Ubuntu 9.04
  • Ubuntu 8.04 LTS


An attacker could view sensitive information in an unlikely circumstance.

Software Description

  • nss - Network Security Service libraries
  • nspr - NetScape Portable Runtime Library


Richard Moore discovered that NSS would sometimes incorrectly match an SSL certificate which had a Common Name that used a wildcard followed by a partial IP address. While it is very unlikely that a Certificate Authority would issue such a certificate, if an attacker were able to perform a man-in-the-middle attack, this flaw could be exploited to view sensitive information. (CVE-2010-3170)

Nelson Bolyard discovered a weakness in the Diffie-Hellman Ephemeral mode (DHE) key exchange implementation which allowed servers to use a too small key length. (CVE-2010-3173)

Update instructions

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

Ubuntu 10.10
libnss3-1d - 3.12.8-0ubuntu0.10.10.1
Ubuntu 10.04 LTS
libnss3-1d - 3.12.8-0ubuntu0.10.04.1
Ubuntu 9.10
libnss3-1d - 3.12.8-0ubuntu0.9.10.1
Ubuntu 9.04
libnss3-1d - 3.12.8-0ubuntu0.9.04.1
Ubuntu 8.04 LTS
libnss3-1d - 3.12.8-0ubuntu0.8.04.1

To update your system, please follow these instructions:

After a standard system update you need to restart any applications that use NSS, such as Firefox, Thunderbird or Evolution, to make all the necessary changes. This update also includes updated NSPR packages to work with the new NSS.