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Ubuntu Security Notice USN-4060-1
July 16, 2019

nss vulnerabilities
==========================================================================

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

- Ubuntu 19.04
- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS

Summary:

Several security issues were fixed in NSS.

Software Description:
- nss: Network Security Service library

Details:

Henry Corrigan-Gibbs discovered that NSS incorrectly handled importing
certain curve25519 private keys. An attacker could use this issue to cause
NSS to crash, resulting in a denial of service, or possibly obtain
sensitive information. (CVE-2019-11719)

Hubert Kario discovered that NSS incorrectly handled PKCS#1 v1.5 signatures
when using TLSv1.3. An attacker could possibly use this issue to trick NSS
into using PKCS#1 v1.5 signatures, contrary to expectations. This issue
only applied to Ubuntu 19.04. (CVE-2019-11727)

Jonas Allmann discovered that NSS incorrectly handled certain p256-ECDH
public keys. An attacker could possibly use this issue to cause NSS to
crash, resulting in a denial of service. (CVE-2019-11729)

Update instructions:

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

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

Ubuntu 18.04 LTS:
  libnss3                         2:3.35-2ubuntu2.3

Ubuntu 16.04 LTS:
  libnss3                         2:3.28.4-0ubuntu0.16.04.6

After a standard system update you need to restart any applications that
use NSS, such as Evolution, to make all the necessary changes.

References:
  https://usn.ubuntu.com/4060-1
  CVE-2019-11719, CVE-2019-11727, CVE-2019-11729

Package Information:
  https://launchpad.net/ubuntu/+source/nss/2:3.42-1ubuntu2.1
  https://launchpad.net/ubuntu/+source/nss/2:3.35-2ubuntu2.3
  https://launchpad.net/ubuntu/+source/nss/2:3.28.4-0ubuntu0.16.04.6