An urllib3 security update has been released for Ubuntu Linux 20.04 LTS.

USN-5812-1: urllib3 vulnerability

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Ubuntu Security Notice USN-5812-1
January 19, 2023

python-urllib3 vulnerability
==========================================================================

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

- Ubuntu 20.04 LTS

Summary:

urllib3 could be made to stop responding if it received specially crafted
network traffic.

Software Description:
- python-urllib3: HTTP library with thread-safe connection pooling

Details:

It was discovered that urllib3 incorrectly handled certain characters
in URLs. A remote attacker could possibly use this issue to cause urllib3
to consume resources, leading to a denial of service.

Update instructions:

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

Ubuntu 20.04 LTS:
python3-urllib3 1.25.8-2ubuntu0.2

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

References:
https://ubuntu.com/security/notices/USN-5812-1
CVE-2021-33503

Package Information:
https://launchpad.net/ubuntu/+source/python-urllib3/1.25.8-2ubuntu0.2