A NSS security update has been released for Ubuntu Linux 14.04 ESM and 12.04 ESM.

USN-4397-2: NSS vulnerability

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Ubuntu Security Notice USN-4397-2
June 17, 2020

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

- Ubuntu 14.04 ESM
- Ubuntu 12.04 ESM

Summary:

NSS could be made to expose sensitive information over the
network.

Software Description:
- nss: Network Security Service library

Details:

USN-4397-1 fixed a vulnerability in NSS. This update provides
the corresponding update for Ubuntu 12.04 ESM and Ubuntu 14.04 ESM.

Original advisory details:

Cesar Pereida Garcia discovered that NSS incorrectly handled DSA key
generation. A local attacker could possibly use this issue to perform a
timing attack and recover DSA keys. (CVE-2020-12399)

Update instructions:

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

Ubuntu 14.04 ESM:
libnss3 2:3.28.4-0ubuntu0.14.04.5+esm5

Ubuntu 12.04 ESM:
libnss3 2:3.28.4-0ubuntu0.12.04.8

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

References:
  https://usn.ubuntu.com/4397-2
  https://usn.ubuntu.com/4397-1
CVE-2020-12399