USN-8811-1: urllib3 vulnerability

Publication date

24 September 2026

Overview

urllib3 could be made to expose sensitive information over the network.


Packages

Details

It was discovered that urllib3 did not correctly strip sensitive HTTP
headers during cross-origin redirects. An attacker could possibly use this
issue to leak sensitive information.

It was discovered that urllib3 did not correctly strip sensitive HTTP
headers during cross-origin redirects. An attacker could possibly use this
issue to leak sensitive information.

Update instructions

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

Learn more about how to get the fixes.

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

Ubuntu Release Package Version
20.04 LTS focal python3-urllib3 –  1.25.8-2ubuntu0.4+esm5  
18.04 LTS bionic python-urllib3 –  1.22-1ubuntu0.18.04.2+esm4  
python3-urllib3 –  1.22-1ubuntu0.18.04.2+esm4  
16.04 LTS xenial python-urllib3 –  1.13.1-2ubuntu0.16.04.4+esm4  
python3-urllib3 –  1.13.1-2ubuntu0.16.04.4+esm4  

Reduce your security exposure

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