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

USN-5436-1: libXrender vulnerabilities

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Ubuntu Security Notice USN-5436-1
May 23, 2022

libxrender 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 libXrender.

Software Description:
- libxrender: X11 Rendering Extension client library

Details:

Tobias Stoeckmann discovered that libXrender incorrectly handled certain
responses. An attacker could possibly use this issue to cause a denial
of service, or possibly execute arbitrary code.
(CVE-2016-7949, CVE-2016-7950)

Update instructions:

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

Ubuntu 16.04 ESM:
libxrender1 1:0.9.9-0ubuntu1+esm1

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

References:
https://ubuntu.com/security/notices/USN-5436-1
CVE-2016-7949, CVE-2016-7950