RHSA-2026:28159

Vulnerability from csaf_redhat - Published: 2026-06-23 10:51 - Updated: 2026-06-23 21:53
Summary
Red Hat Security Advisory: python3.12-urllib3 security update
Severity
Important
Notes
Topic: An update for python3.12-urllib3 is now available for Red Hat Enterprise Linux 9. 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.
Details: 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: Denial of Service due to excessive HTTP response decompression (CVE-2026-44432) * urllib3: urllib3: Information disclosure via cross-origin redirects forwarding sensitive headers (CVE-2026-44431) 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.
Terms of Use: This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original.
CVE-2026-44431

A flaw was found in urllib3, an HTTP client library for Python. When using the low-level API via `ProxyManager.connection_from_url().urlopen()` with `assert_same_host=False`, cross-origin redirects can still forward sensitive headers. This could allow a remote attacker to gain unauthorized access to sensitive information.

5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
CWE-201 - Insertion of Sensitive Information Into Sent Data
Affected products
Product Identifier Version Remediation
Unresolved product id: AppStream-9.8.0.Z.MAIN.EUS:python3.12-urllib3-0:1.26.19-3.el9_8.noarch —
Vendor Fix fix
Unresolved product id: AppStream-9.8.0.Z.MAIN.EUS:python3.12-urllib3-0:1.26.19-3.el9_8.src —
Vendor Fix fix
Threats
Impact Moderate
CVE-2026-44432

A flaw was found in urllib3, an HTTP client library for Python. This vulnerability allows a remote attacker to cause excessive resource consumption, such as high CPU usage and massive memory allocation, on the client side. This occurs when urllib3 attempts to decompress an entire HTTP response, even if only a partial read was requested, or when draining the connection after a partial decompression. This can lead to a Denial of Service (DoS) condition.

7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE-409 - Improper Handling of Highly Compressed Data (Data Amplification)
Affected products
Product Identifier Version Remediation
Unresolved product id: AppStream-9.8.0.Z.MAIN.EUS:python3.12-urllib3-0:1.26.19-3.el9_8.noarch —
Vendor Fix fix
Unresolved product id: AppStream-9.8.0.Z.MAIN.EUS:python3.12-urllib3-0:1.26.19-3.el9_8.src —
Vendor Fix fix
Threats
Impact Important
References
To clipboard 

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}


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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.