USN-4636-1: LibVNCServer, Vino vulnerability

Releases

• Ubuntu 20.10
• Ubuntu 20.04 LTS
• Ubuntu 18.04 ESM
• Ubuntu 16.04 ESM

Packages

• libvncserver - vnc server library
• vino - VNC server for GNOME

Details

It was discovered that LibVNCServer incorrectly handled certain internals.
An attacker could possibly use this issue to cause a denial of service.
This issue only affected Ubuntu 16.04 LTS, Ubuntu 18.04 LTS and Ubuntu 20.04 LTS.

Vino package ships with a LibVNCServer source and all listed releases were
affected for this package.

Update instructions

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

Ubuntu 20.10

• vino - 3.22.0-6ubuntu2.1

Ubuntu 20.04

• libvncclient1 - 0.9.12+dfsg-9ubuntu0.3
• libvncserver1 - 0.9.12+dfsg-9ubuntu0.3
• vino - 3.22.0-5ubuntu2.2

Ubuntu 18.04

• libvncclient1 - 0.9.11+dfsg-1ubuntu1.4
• libvncserver1 - 0.9.11+dfsg-1ubuntu1.4
• vino - 3.22.0-3ubuntu1.2

Ubuntu 16.04

• libvncclient1 - 0.9.10+dfsg-3ubuntu0.16.04.6
• libvncserver1 - 0.9.10+dfsg-3ubuntu0.16.04.6
• vino - 3.8.1-0ubuntu9.4

In general, a standard system update will make all the necessary changes.

References

• CVE-2020-25708