A Jinja2 security update has been released for Ubuntu Linux 16.04 ESM.

USN-5701-1: Jinja2 vulnerability

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Ubuntu Security Notice USN-5701-1
October 26, 2022

jinja2 vulnerability
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 16.04 ESM

Summary:

Jinja2 could be made to hang if it received specially crafted input.

Software Description:
- jinja2: small but fast and easy to use stand-alone template engine

Details:

Yeting Li discovered that Jinja2 incorrectly handled certain inputs.
An attacker could possibly use this issue to cause a denial of service.

Update instructions:

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

Ubuntu 16.04 ESM:
python-jinja2 2.8-1ubuntu0.1+esm1
python3-jinja2 2.8-1ubuntu0.1+esm1

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

References:
https://ubuntu.com/security/notices/USN-5701-1
CVE-2020-28493