python: cpython: Python: Arbitrary code execution via command injection in webbrowser.open() API

A flaw was found in the Python webbrowser.open API. If a specially crafted URL containing "%action" is processed, an attacker could bypass a previous mitigation for CVE-2026-4519. This bypass allows for command injection into the underlying shell, potentially leading to arbitrary code execution...

CLSA-2026-1777946894 Fix CVE(s): CVE-2022-0391, CVE-2022-45061, CVE-2024-7592, CVE-2026-4519

SECURITY UPDATE: URL parsing accepts ASCII tab/CR/LF URL smuggling - debian/patches/CVE-2022-0391.patch: sanitise tab, CR, LF anywhere in URL/scheme inside urlsplit before cache lookup, plus regression test in Lib/urlparse.py, Lib/test/testurlparse.py. - CVE-2022-0391 SECURITY UPDATE: Quadratic...

CLSA-2026-1777946871 python: Fix of CVE-2026-4519

CVE-2026-4519: reject leading dashes in webbrowser URLs that could be treated as command-line options by external browsers; also close a %action-substitution bypass of the check in UnixBrowser.open...

CLSA-2026-1777946712 python: Fix of CVE-2026-4519

CVE-2026-4519: reject leading dashes in webbrowser URLs that could be treated as command-line options by external browsers; also close a %action-substitution bypass of the check in UnixBrowser.open...

CLSA-2026-1777944317 Fix CVE(s): CVE-2025-8194, CVE-2026-4519, CVE-2026-4786

SECURITY UPDATE: tarfile DoS via negative member offsets - debian/patches/CVE-2025-8194.patch: validate that member offsets are non-negative in Lib/tarfile.py. - CVE-2025-8194 SECURITY UPDATE: webbrowser.open accepts URLs with leading dashes - debian/patches/CVE-2026-4519-CVE-2026-4786.patch:...

CLSA-2026-1777944042 Fix CVE(s): CVE-2025-8194, CVE-2026-4519, CVE-2026-4786

SECURITY UPDATE: tarfile DoS via negative member offsets - debian/patches/CVE-2025-8194.patch: validate that member offsets are non-negative in Lib/tarfile.py. - CVE-2025-8194 SECURITY UPDATE: webbrowser.open accepts URLs with leading dashes - debian/patches/CVE-2026-4519-CVE-2026-4786.patch:...

CLSA-2026-1777891107 python3.11: Fix of CVE-2026-4786

CVE-2026-4786: fix webbrowser %action substitution bypass of the dash-prefix safety check by validating the post-substitution URL and expanding %action before %s in UnixBrowser argument assembly...

CLSA-2026-1777883384 python3.11: Fix of CVE-2026-4786

CVE-2026-4786: fix webbrowser %action substitution bypass of dash-prefix check by validating url after %action expansion and reordering replace calls so the dash-prefix check sees the final argument...

MiracleLinux 9 : python3.12-3.12.12-4.el9_7.3 (AXSA:2026-519:12)

The remote MiracleLinux 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the AXSA:2026-519:12 advisory. python: Python: Arbitrary code execution or information disclosure via use-after-free in decompression modules CVE-2026-6100 python: cpython: Python:...

MiracleLinux 9 : python3.11-3.11.13-5.3.el9_7 (AXSA:2026-521:09)

The remote MiracleLinux 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the AXSA:2026-521:09 advisory. python: Python: Arbitrary code execution or information disclosure via use-after-free in decompression modules CVE-2026-6100 python: cpython: Python:...

MiracleLinux 8 : python3.11-3.11.13-7.el8_10 (AXSA:2026-522:10)

The remote MiracleLinux 8 host has packages installed that are affected by multiple vulnerabilities as referenced in the AXSA:2026-522:10 advisory. python: Python: Arbitrary code execution or information disclosure via use-after-free in decompression modules CVE-2026-6100 python: cpython: Python:...

CLSA-2026-1777660095 python3.9: Fix of CVE-2026-4786

CVE-2026-4786: fix webbrowser %action substitution bypass of dash-prefix check...

CLSA-2026-1777548617 Fix CVE(s): CVE-2026-4519, CVE-2026-4786

SECURITY UPDATE: webbrowser.open accepts URLs with leading dashes - debian/patches/CVE-2026-4519-CVE-2026-4786.patch: reject URLs whose lstrip starts with '-' in Lib/webbrowser.py; also fix bypass via %action substitution in UnixBrowser.open. - CVE-2026-4519 - CVE-2026-4786...

CLSA-2026-1777548458 Fix CVE(s): CVE-2026-4519, CVE-2026-4786

SECURITY UPDATE: webbrowser.open accepts URLs with leading dashes - debian/patches/CVE-2026-4519-CVE-2026-4786.patch: reject URLs whose lstrip starts with '-' in Lib/webbrowser.py; also fix bypass via %action substitution in UnixBrowser.open. - CVE-2026-4519 - CVE-2026-4786...

Important: python3.12

Issue Overview: The fix for CVE-2026-0672, which rejected control characters in http.cookies.Morsel, was incomplete. The Morsel.update, |= operator, and unpickling paths were not patched, allowing control characters to bypass input validation. Additionally, BaseCookie.jsoutput lacked the output...

Important: python3.9

Issue Overview: The fix for CVE-2026-0672, which rejected control characters in http.cookies.Morsel, was incomplete. The Morsel.update, |= operator, and unpickling paths were not patched, allowing control characters to bypass input validation. Additionally, BaseCookie.jsoutput lacked the output...

AlmaLinux 10 : python3.12 (ALSA-2026:10711)

The remote AlmaLinux 10 host has packages installed that are affected by multiple vulnerabilities as referenced in the ALSA-2026:10711 advisory. python: Python: Arbitrary code execution or information disclosure via use-after-free in decompression modules CVE-2026-6100 python: cpython: Python:...

AlmaLinux 9 : python3.9 (ALSA-2026:10949)

The remote AlmaLinux 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the ALSA-2026:10949 advisory. python: Python: Arbitrary code execution or information disclosure via use-after-free in decompression modules CVE-2026-6100 python: cpython: Python:...

AlmaLinux 9 : python3.11 (ALSA-2026:10774)

The remote AlmaLinux 9 host has packages installed that are affected by multiple vulnerabilities as referenced in the ALSA-2026:10774 advisory. python: Python: Arbitrary code execution or information disclosure via use-after-free in decompression modules CVE-2026-6100 python: cpython: Python:...

Amazon Linux 2023 : python3.11, python3.11-devel, python3.11-idle (ALAS2023-2026-1620)

It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2023-2026-1620 advisory. The fix for CVE-2026-0672, which rejected control characters in http.cookies.Morsel, was incomplete. The Morsel.update, |= operator, and unpickling paths were not patched, allowing control...