A libxml2 security update has been released for Ubuntu Linux 16.04 ESM, 18.04 LTS, and 20.04 LTS.

USN-5548-1: libxml2 vulnerability

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Ubuntu Security Notice USN-5548-1
August 04, 2022

libxml2 vulnerability
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 20.04 LTS
- Ubuntu 18.04 LTS
- Ubuntu 16.04 ESM

Summary:

libxml2 could be made to execute arbitrary code if it received
a specially crafted file.

Software Description:
- libxml2: GNOME XML library

Details:

It was discovered that libxml2 incorrectly handled certain XML files.
An attacker could possibly use this issue to execute arbitrary code.

Update instructions:

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

Ubuntu 20.04 LTS:
libxml2 2.9.10+dfsg-5ubuntu0.20.04.4
libxml2-utils 2.9.10+dfsg-5ubuntu0.20.04.4

Ubuntu 18.04 LTS:
libxml2 2.9.4+dfsg1-6.1ubuntu1.7
libxml2-utils 2.9.4+dfsg1-6.1ubuntu1.7

Ubuntu 16.04 ESM:
libxml2 2.9.3+dfsg1-1ubuntu0.7+esm3
libxml2-utils 2.9.3+dfsg1-1ubuntu0.7+esm3

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

References:
  https://ubuntu.com/security/notices/USN-5548-1
CVE-2016-3709

Package Information:
  https://launchpad.net/ubuntu/+source/libxml2/2.9.10+dfsg-5ubuntu0.20.04.4
  https://launchpad.net/ubuntu/+source/libxml2/2.9.4+dfsg1-6.1ubuntu1.7