USN-4397-1: NSS vulnerabilities

Publication date

16 June 2020

Overview

Several security issues were fixed in NSS.


Packages

  • nss - Network Security Service library

Details

It was discovered that NSS incorrectly handled the TLS State Machine. A
remote attacker could possibly use this issue to cause NSS to hang,
resulting in a denial of service. This issue only affected Ubuntu 18.04 LTS
and Ubuntu 19.10. (CVE-2019-17023)

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)

It was discovered that NSS incorrectly handled the TLS State Machine. A
remote attacker could possibly use this issue to cause NSS to hang,
resulting in a denial of service. This issue only affected Ubuntu 18.04 LTS
and Ubuntu 19.10. (CVE-2019-17023)

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

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

Learn more about how to get the fixes.

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

Ubuntu Release Package Version
20.04 focal libnss3 –  2:3.49.1-1ubuntu1.1
19.10 eoan libnss3 –  2:3.45-1ubuntu2.3
18.04 bionic libnss3 –  2:3.35-2ubuntu2.8
16.04 xenial libnss3 –  2:3.28.4-0ubuntu0.16.04.11

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