USN-7955-1: urllib3 vulnerability

Publication date

12 January 2026

Overview

urllib3 could be made to use excessive resources if it received specially crafted network traffic.


Packages

Details

It was discovered that urllib3 incorrectly handled decompression during
HTTP redirects. An attacker could possibly use this issue to cause urllib3
to use excessive resources, causing a denial of service.

It was discovered that urllib3 incorrectly handled decompression during
HTTP redirects. An attacker could possibly use this issue to cause urllib3
to use excessive resources, causing a denial of service.

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
25.10 questing python3-urllib3 –  2.3.0-3ubuntu0.2
25.04 plucky python3-urllib3 –  2.3.0-2ubuntu0.3
24.04 LTS noble python3-urllib3 –  2.0.7-1ubuntu0.4
22.04 LTS jammy python3-urllib3 –  1.26.5-1~exp1ubuntu0.5
20.04 LTS focal python3-urllib3 –  1.25.8-2ubuntu0.4+esm3  

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