A denial-of-service vulnerability (CVE-2025-69534, CVSS 7.5 HIGH) exists in python-markdown where an attacker can cause a service disruption by processing malformed HTML-like sequences. The NVD lists python-markdown version 3.8 as affected, but the article does not specify the exact vulnerable or fixed version ranges for the Red Hat packages. Red Hat has released a security update rated Important to address this issue for python-markdown on Red Hat Enterprise Linux 10.0 Extended Update Support.
Red Hat Product Errata RHSA-2026:20677 - Security Advisory Issued: 2026-05-26 Updated: 2026-05-26 RHSA-2026:20677 - Security Advisory Overview Updated Packages Synopsis Important: python-markdown security update Type/Severity Security Advisory: Important Red Hat Lightspeed patch analysis Identify and remediate systems affected by this advisory. View affected systems Topic An update for python-markdown is now available for Red Hat Enterprise Linux 10.0 Extended 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): python-markdown: denial of service via malformed HTML-like sequences (CVE-2025-69534) 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 - Extended Update Support 10.0 x86_64 Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 10.0 s390x Red Hat Enterprise Linux for Power, little endian - Extended Update Support 10.0 ppc64le Red Hat Enterprise Linux for ARM 64 - Extended Update Support 10.0 aarch64 Red Hat Enterprise Linux for ARM 64 - 4 years of updates 10.0 aarch64 Red Hat Enterprise Linux for IBM z Systems - 4 years of updates 10.0 s390x Red Hat Enterprise Linux for Power, little endian - 4 years of support 10.0 ppc64le Red Hat Enterprise Linux for x86_64 - 4 years of updates 10.0 x86_64 Fixes BZ - 2444839 - CVE-2025-69534 python-markdown: denial of service via malformed HTML-like sequences CVEs CVE-2025-69534 References https://access.redhat.com/security/updates/classification/#important Note: More recent versions of these packages may be available. 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Red Hat Enterprise Linux for x86_64 - Extended Update Support 10.0 SRPM python-markdown-3.5.1-6.el10_0.1.src.rpm SHA-256: e0b33087534a029f160ca789de4acbf66ef4415769f6951ae175e9bb802e40d8 x86_64 python3-markdown-3.5.1-6.el10_0.1.noarch.rpm SHA-256: 311be451220560d7be8cd7397c9bf48be7116034435663bd2f46f23eb8e70a6d Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 10.0 SRPM python-markdown-3.5.1-6.el10_0.1.src.rpm SHA-256: e0b33087534a029f160ca789de4acbf66ef4415769f6951ae175e9bb802e40d8 s390x python3-markdown-3.5.1-6.el10_0.1.noarch.rpm SHA-256: 311be451220560d7be8cd7397c9bf48be7116034435663bd2f46f23eb8e70a6d Red Hat Enterprise Linux for Power, little endian - Extended Update Support 10.0 SRPM python-markdown-3.5.1-6.el10_0.1.src.rpm SHA-256: e0b33087534a029f160ca789de4acbf66ef4415769f6951ae175e9bb802e40d8 ppc64le python3-markdown-3.5.1-6.el10_0.1.noarch.rpm SHA-256: 311be451220560d7be8cd7397c9bf48be7116034435663bd2f46f23eb8e70a6d Red Hat Enterprise Linux for ARM 64 - Extended Update Support 10.0 SRPM python-markdown-3.5.1-6.el10_0.1.src.rpm SHA-256: e0b33087534a029f160ca789de4acbf66ef4415769f6951ae175e9bb802e40d8 aarch64 python3-markdown-3.5.1-6.el10_0.1.noarch.rpm SHA-256: 311be451220560d7be8cd7397c9bf48be7116034435663bd2f46f23eb8e70a6d Red Hat Enterprise Linux for ARM 64 - 4 years of updates 10.0 SRPM python-markdown-3.5.1-6.el10_0.1.src.rpm SHA-256: e0b33087534a029f160ca789de4acbf66ef4415769f6951ae175e9bb802e40d8 aarch64 python3-markdown-3.5.1-6.el10_0.1.noarch.rpm SHA-256: 311be451220560d7be8cd7397c9bf48be7116034435663bd2f46f23eb8e70a6d Red Hat Enterprise Linux for IBM z Systems - 4 years of updates 10.0 SRPM python-markdown-3.5.1-6.el10_0.1.src.rpm SHA-256: e0b33087534a029f160ca789de4acbf66ef4415769f6951ae175e9bb802e40d8 s390x python3-markdown-3.5.1-6.el10_0.1.noarch.rpm SHA-256: 311be451220560d7be8cd7397c9bf48be7116034435663bd2f46f23eb8e70a6d Red Hat Enterprise Linux for Power, little endian - 4 years of support 10.0 SRPM python-markdown-3.5.1-6.el10_0.1.src.rpm SHA-256: e0b33087534a029f160ca789de4acbf66ef4415769f6951ae175e9bb802e40d8 ppc64le python3-markdown-3.5.1-6.el10_0.1.noarch.rpm SHA-256: 311be451220560d7be8cd7397c9bf48be7116034435663bd2f46f23eb8e70a6d Red Hat Enterprise Linux for x86_64 - 4 years of updates 10.0 SRPM python-markdown-3.5.1-6.el10_0.1.src.rpm SHA-256: e0b33087534a029f160ca789de4acbf66ef4415769f6951ae175e9bb802e40d8 x86_64 python3-markdown-3.5.1-6.el10_0.1.noarch.rpm SHA-256: 311be451220560d7be8cd7397c9bf48be7116034435663bd2f46f23eb8e70a6d The Red Hat security contact is secalert@redhat.com . More contact details at https://access.redhat.com/security/team/contact/ .