=========================================================================Ubuntu Security Notice USN-3877-1
January 31, 2019

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

- Ubuntu 18.10
- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS
- Ubuntu 14.04 LTS

Summary:

Several security issues were fixed in LibVNCServer.

Software Description:
- libvncserver: vnc server library

Details:

It was discovered that LibVNCServer incorrectly handled certain operations.
A remote attacker able to connect to applications using LibVNCServer could
possibly use this issue to obtain sensitive information, cause a denial of
service, or execute arbitrary code.

Update instructions:

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

Ubuntu 18.10:
  libvncclient1                   0.9.11+dfsg-1.1ubuntu0.1
  libvncserver1                   0.9.11+dfsg-1.1ubuntu0.1

Ubuntu 18.04 LTS:
  libvncclient1                   0.9.11+dfsg-1ubuntu1.1
  libvncserver1                   0.9.11+dfsg-1ubuntu1.1

Ubuntu 16.04 LTS:
  libvncclient1                   0.9.10+dfsg-3ubuntu0.16.04.3
  libvncserver1                   0.9.10+dfsg-3ubuntu0.16.04.3

Ubuntu 14.04 LTS:
  libvncserver0                   0.9.9+dfsg-1ubuntu1.4

After a standard system update you need to restart LibVNCServer
applications to make all the necessary changes.

References:
  https://ubuntu.com/security/notices/USN-3877-1
  CVE-2018-15126, CVE-2018-15127, CVE-2018-20019, CVE-2018-20020,
  CVE-2018-20021, CVE-2018-20022, CVE-2018-20023, CVE-2018-20024,
  CVE-2018-20748, CVE-2018-20749, CVE-2018-20750, CVE-2018-6307

Package Information:
  https://launchpad.net/ubuntu/+source/libvncserver/0.9.11+dfsg-1.1ubuntu0.1
  https://launchpad.net/ubuntu/+source/libvncserver/0.9.11+dfsg-1ubuntu1.1
  https://launchpad.net/ubuntu/+source/libvncserver/0.9.10+dfsg-3ubuntu0.16.04.3
  https://launchpad.net/ubuntu/+source/libvncserver/0.9.9+dfsg-1ubuntu1.4