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Fedora 42 python3.12 Critical Arbitrary Code Execution Vuln 2026

Linuxsecurity •LinuxSecurity Advisories • April 20, 2026

Python 3.12 is an accessible, high-level, dynamically typed, interpreted programming language, designed with an emphasis on code readability. It includes an extensive standard library, and has a vast ecosystem of third-party libraries. The python3.12 package provides the "python3.12" executable: the reference interpreter for the Python language, version 3. The majority of its standard library is provided in the python3.12-libs package, which should be installed automatically along with python3.12. The remaining parts of the Python standard library are broken out into the python3.12-tkinter and python3.12-test packages, which may need to be installed separately. Documentation for Python is provided in the python3.12-docs package. Packages containing additional libraries for Python are generally named with the "python3.12-" prefix. Update Information : Security fixes for CVE-2026-1502, CVE-2026-4786, CVE-2026-6100, CVE-2026-2297, CVE-2026-3644, CVE-2026-4224

Python 3.12 is an accessible, high-level, dynamically typed, interpreted

programming language, designed with an emphasis on code readability.

It includes an extensive standard library, and has a vast ecosystem of

third-party libraries.

The python3.12 package provides the "python3.12" executable: the reference

interpreter for the Python language, version 3.

The majority of its standard library is provided in the python3.12-libs package,

which should be installed automatically along with python3.12.

The remaining parts of the Python standard library are broken out into the

python3.12-tkinter and python3.12-test packages, which may need to be installed

Documentation for Python is provided in the python3.12-docs package.

Packages containing additional libraries for Python are generally named with

the "python3.12-" prefix.

Security fixes for CVE-2026-1502, CVE-2026-4786, CVE-2026-6100, CVE-2026-2297, CVE-2026-3644, CVE-2026-4224

* Thu Apr 16 2026 Charalampos Stratakis - 3.12.13-3 - Security fixes for CVE-2026-1502, CVE-2026-4786, CVE-2026-6100, CVE-2026-2297, CVE-2026-3644, CVE-2026-4224 Resolves: rhbz#2444705, rhbz#2448189, rhbz#2448205, rhbz#2457942, rhbz#2458014, rhbz#2458222

[ 1 ] Bug #2444705 - CVE-2026-2297 python3.12: CPython: Logging Bypass in Legacy .pyc File Handling [fedora-all] [ 2 ] Bug #2448189 - CVE-2026-3644 python3.12: Incomplete control character validation in http.cookies [fedora-all] [ 3 ] Bug #2448205 - CVE-2026-4224 python3.12: Stack overflow parsing XML with deeply nested DTD content models [fedora-all] [ 4 ] Bug #2457942 - CVE-2026-1502 python3.12: Python: HTTP header injection via CR/LF in proxy tunnel headers [fedora-all] [ 5 ] Bug #2458014 - CVE-2026-6100 python3.12: Python: Arbitrary code execution or information disclosure via use-after-free in decompression modules [fedora-all] [ 6 ] Bug #2458222 - CVE-2026-4786... Read the Full Advisory

This update can be installed with the "dnf" update program. Use su -c 'dnf upgrade --advisory FEDORA-2026-30fbc5a8b2' at the command line. For more information, refer to the dnf documentation available at

The full story

This article is one source in a clustered incident — the cluster page carries the summary, timeline and every other outlet covering it.

Critical Python Vulnerabilities Affect Multiple Versions Recent security updates for Python 3.10, 3.12, and 3.15 address critical vulnerabilities impacting various systems. Key vulnerabilities include CVE-2026-1502, which allows HTTP header injection, and CVE-2026-6100, which can lead to arbitrary code execution. These vulnerabilities affect multiple distributions, including Ubuntu 22.04 and Fedora 42 and 43. The vulnerabilities were published between March 4 and April 13, 2026, with patches released shortly after. Systems using these Python versions are at risk if not updated promptly. The updates include fixes for logging bypass and stack overflow issues as well. Security teams are urged to apply the updates to mitigate potential exploitation risks. The situation remains critical as attackers may exploit these vulnerabilities before widespread patch adoption. 11 sources 74

Extracted Entities

Companies (1)

Fedora

CVEs (6)

CVE-2026-1502 CVE-2026-2297 CVE-2026-3644 CVE-2026-4224 CVE-2026-4786 CVE-2026-6100