An OpenSSH security update has been released for Ubuntu Linux 16.04 ESM.

USN-5666-1: OpenSSH vulnerability

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Ubuntu Security Notice USN-5666-1
October 10, 2022

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

- Ubuntu 16.04 ESM

Summary:

OpenSSH could be made to run arbitrary code if it some
non-default configuration are in use.

Software Description:
- openssh: secure shell (SSH) for secure access to remote machines

Details:

It was discovered that OpenSSH incorrectly handled certain helper programs.
An attacker could possibly use this issue to arbitrary code execution.

Update instructions:

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

Ubuntu 16.04 ESM:
openssh-server 1:7.2p2-4ubuntu2.10+esm2

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

References:
  https://ubuntu.com/security/notices/USN-5666-1
CVE-2021-41617