A NSS security update has been released for Ubuntu Linux 19.04, 18.04 LTS, 16.04 LTS, 14.04 ESM, and 12.04 ESM

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Ubuntu Security Notice USN-4215-1
December 09, 2019

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

- Ubuntu 19.04
- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS
- Ubuntu 14.04 ESM
- Ubuntu 12.04 ESM

Summary:

NSS could be made to crash if it received a specially crafted certificate.

Software Description:
- nss: Network Security Service library

Details:

It was discovered that NSS incorrectly handled certain certificates.
An attacker could possibly use this issue to cause a denial of service.

Update instructions:

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

Ubuntu 19.04:
libnss3 2:3.42-1ubuntu2.4

Ubuntu 18.04 LTS:
libnss3 2:3.35-2ubuntu2.6

Ubuntu 16.04 LTS:
libnss3 2:3.28.4-0ubuntu0.16.04.9

Ubuntu 14.04 ESM:
libnss3 2:3.28.4-0ubuntu0.14.04.5+esm3

Ubuntu 12.04 ESM:
libnss3 2:3.28.4-0ubuntu0.12.04.6

After a standard system update you need to reboot your computer to make
all the necessary changes.

References:
  https://usn.ubuntu.com/4215-1
CVE-2019-17007

Package Information:
  https://launchpad.net/ubuntu/+source/nss/2:3.42-1ubuntu2.4
  https://launchpad.net/ubuntu/+source/nss/2:3.35-2ubuntu2.6
  https://launchpad.net/ubuntu/+source/nss/2:3.28.4-0ubuntu0.16.04.9