RHSA-2026:19177 - Security Advisory

Topic

An update for python3.12 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.

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):

• expat: libexpat in Expat allows attackers to trigger large dynamic memory allocations via a small document that is submitted for parsing (CVE-2025-59375)
• python: Quadratic complexity in os.path.expandvars() with user-controlled template (CVE-2025-6075)
• cpython: Out-of-memory when loading Plist (CVE-2025-13837)
• cpython: Header injection via newlines in data URL mediatype in Python (CVE-2025-15282)
• cpython: Header injection in http.cookies.Morsel in Python (CVE-2026-0672)
• cpython: CPython: Logging Bypass in Legacy .pyc File Handling (CVE-2026-2297)
• cpython: Incomplete control character validation in http.cookies (CVE-2026-3644)
• cpython: Stack overflow parsing XML with deeply nested DTD content models (CVE-2026-4224)
• python: Python: Command-line option injection in webbrowser.open() via crafted URLs (CVE-2026-4519)
• python: Python: HTTP header injection via CR/LF in proxy tunnel headers (CVE-2026-1502)
• python: Python: Arbitrary code execution or information disclosure via use-after-free in decompression modules (CVE-2026-6100)
• python: cpython: Python: Arbitrary code execution via command injection in webbrowser.open() API (CVE-2026-4786)

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.

Solution

For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

Affected Products

• Red Hat Enterprise Linux for x86_64 9 x86_64
• Red Hat Enterprise Linux for x86_64 - Extended Update Support 9.8 x86_64
• Red Hat Enterprise Linux for IBM z Systems 9 s390x
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 9.8 s390x
• Red Hat Enterprise Linux for Power, little endian 9 ppc64le
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 9.8 ppc64le
• Red Hat Enterprise Linux for ARM 64 9 aarch64
• Red Hat Enterprise Linux for ARM 64 - Extended Update Support 9.8 aarch64
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 9.8 ppc64le
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 9.8 x86_64
• Red Hat CodeReady Linux Builder for x86_64 9 x86_64
• Red Hat CodeReady Linux Builder for Power, little endian 9 ppc64le
• Red Hat CodeReady Linux Builder for ARM 64 9 aarch64
• Red Hat CodeReady Linux Builder for IBM z Systems 9 s390x
• Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support 9.8 x86_64
• Red Hat CodeReady Linux Builder for Power, little endian - Extended Update Support 9.8 ppc64le
• Red Hat CodeReady Linux Builder for IBM z Systems - Extended Update Support 9.8 s390x
• Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support 9.8 aarch64
• Red Hat Enterprise Linux for ARM 64 - 4 years of updates 9.8 aarch64
• Red Hat Enterprise Linux for IBM z Systems - 4 years of updates 9.8 s390x
• Red Hat Enterprise Linux for x86_64 - Extended Life Cycle 9.8 x86_64
• Red Hat Enterprise Linux for ARM 64 - Extended Life Cycle 9.8 aarch64
• Red Hat Enterprise Linux for Power, little endian - Extended Life Cycle 9.8 ppc64le
• Red Hat Enterprise Linux for IBM z Systems - Extended Life Cycle 9.8 s390x

Fixes

• BZ - 2395108 - CVE-2025-59375 firefox: thunderbird: expat: libexpat in Expat allows attackers to trigger large dynamic memory allocations via a small document that is submitted for parsing
• BZ - 2408891 - CVE-2025-6075 python: Quadratic complexity in os.path.expandvars() with user-controlled template
• BZ - 2418084 - CVE-2025-13837 cpython: Out-of-memory when loading Plist
• BZ - 2431366 - CVE-2025-15282 cpython: Header injection via newlines in data URL mediatype in Python
• BZ - 2431374 - CVE-2026-0672 cpython: Header injection in http.cookies.Morsel in Python
• BZ - 2444691 - CVE-2026-2297 cpython: CPython: Logging Bypass in Legacy .pyc File Handling
• BZ - 2448168 - CVE-2026-3644 cpython: Incomplete control character validation in http.cookies
• BZ - 2448181 - CVE-2026-4224 cpython: Stack overflow parsing XML with deeply nested DTD content models
• BZ - 2449649 - CVE-2026-4519 python: Python: Command-line option injection in webbrowser.open() via crafted URLs
• BZ - 2457409 - CVE-2026-1502 python: Python: HTTP header injection via CR/LF in proxy tunnel headers
• BZ - 2457932 - CVE-2026-6100 python: Python: Arbitrary code execution or information disclosure via use-after-free in decompression modules
• BZ - 2458049 - CVE-2026-4786 python: cpython: Python: Arbitrary code execution via command injection in webbrowser.open() API

CVEs

• CVE-2025-6075
• CVE-2025-13837
• CVE-2025-15282
• CVE-2025-59375
• CVE-2026-0672
• CVE-2026-1502
• CVE-2026-2297
• CVE-2026-3644
• CVE-2026-4224
• CVE-2026-4519
• CVE-2026-4786
• CVE-2026-6100

References

• https://access.redhat.com/security/updates/classification/#important