A pip regression update has been released for Ubuntu Linux 14.04 ESM, 16.04 ESM, and 18.04 LTS.

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Ubuntu Security Notice USN-5821-4
March 02, 2023

python-pip regression
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 18.04 LTS
- Ubuntu 16.04 ESM
- Ubuntu 14.04 ESM

Summary:

USN-5821-3 caused a minor regression in pip.

Software Description:
- python-pip: Python package installer

Details:

USN-5821-3 fixed a vulnerability in pip. The update introduced
a minor regression in Ubuntu 14.04 ESM, Ubuntu 16.04 ESM and
Ubuntu 18.04 LTS. This update fixes the problem.

We apologize for the inconvenience.

Original advisory details:

Sebastian Chnelik discovered that wheel incorrectly handled
certain file names when validated against a regex expression.
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 18.04 LTS:
python-pip 9.0.1-2.3~ubuntu1.18.04.8
python-pip-whl 9.0.1-2.3~ubuntu1.18.04.8
python3-pip 9.0.1-2.3~ubuntu1.18.04.8

Ubuntu 16.04 ESM:
python-pip 8.1.1-2ubuntu0.6+esm5
python-pip-whl 8.1.1-2ubuntu0.6+esm5
python3-pip 8.1.1-2ubuntu0.6+esm5

Ubuntu 14.04 ESM:
python-pip 1.5.4-1ubuntu4+esm4
python-pip-whl 1.5.4-1ubuntu4+esm4
python3-pip 1.5.4-1ubuntu4+esm4

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

References:
https://ubuntu.com/security/notices/USN-5821-4
https://ubuntu.com/security/notices/USN-5821-1

Package Information:
https://launchpad.net/ubuntu/+source/python-pip/9.0.1-2.3~ubuntu1.18.04.8