A Graphviz security update has been released for Ubuntu Linux 16.04 ESM.

USN-5264-1: Graphviz vulnerabilities

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Ubuntu Security Notice USN-5264-1
February 03, 2022

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

- Ubuntu 16.04 ESM

Summary:

Several security issues were fixed in graphviz.

Software Description:
- graphviz: rich set of graph drawing tools

Details:

It was discovered that graphviz contains null pointer dereference
vulnerabilities. Exploitation via a specially crafted input file
can cause a denial of service.
(CVE-2018-10196, CVE-2019-11023)

It was discovered that graphviz contains a buffer overflow
vulnerability. Exploitation via a specially crafted input file can cause
a denial of service or possibly allow for arbitrary code execution.
(CVE-2020-18032)

Update instructions:

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

Ubuntu 16.04 ESM:
graphviz 2.38.0-12ubuntu2.1+esm1
libcdt5 2.38.0-12ubuntu2.1+esm1
libcgraph6 2.38.0-12ubuntu2.1+esm1
libgvc6 2.38.0-12ubuntu2.1+esm1
libgvc6-plugins-gtk 2.38.0-12ubuntu2.1+esm1
libgvpr2 2.38.0-12ubuntu2.1+esm1
libpathplan4 2.38.0-12ubuntu2.1+esm1
libxdot4 2.38.0-12ubuntu2.1+esm1

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

References:
https://ubuntu.com/security/notices/USN-5264-1
CVE-2018-10196, CVE-2019-11023, CVE-2020-18032