RHSA-2026:2728 — Security Advisory
Red Hat Security Advisory: python-urllib3 security update
Severity
ImportantRed Hat Product Security
Products
Official CSAF product identity
Published · February 16, 2026
Updated · November 4, 2026
Topic
An update for python-urllib3 is now available for Red Hat Enterprise Linux 8.2 Advanced Update Support.
Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.
Description
Python is an interpreted, interactive, object-oriented programming language, which includes modules, classes, exceptions, very high level dynamic data types and dynamic typing. Python supports interfaces to many system calls and libraries, as well as to various windowing systems.
Security Fix(es):
-
urllib3: urllib3: Unbounded decompression chain leads to resource exhaustion (CVE-2025-66418)
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urllib3: urllib3 Streaming API improperly handles highly compressed data (CVE-2025-66471)
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urllib3: urllib3 vulnerable to decompression-bomb safeguard bypass when following HTTP redirects (streaming API) (CVE-2026-21441)
For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.