Red Hat Product Errata RHSA-2026:40856 - Security Advisory Issued: 2026-07-16 Updated: 2026-07-16 RHSA-2026:40856 - Security Advisory Overview Updated Packages Synopsis Important: python3.14 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 python3.14 is now available for Red Hat Enterprise Linux 10. 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: Python: CPU Denial of Service in HTML parser via repeated unterminated markup declarations (CVE-2026-15308) 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 10 x86_64 Red Hat Enterprise Linux for x86_64 - Extended Update Support 10.2 x86_64 Red Hat Enterprise Linux for IBM z Systems 10 s390x Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 10.2 s390x Red Hat Enterprise Linux for Power, little endian 10 ppc64le Red Hat Enterprise Linux for Power, little endian - Extended Update Support 10.2 ppc64le Red Hat Enterprise Linux for ARM 64 10 aarch64 Red Hat Enterprise Linux for ARM 64 - Extended Update Support 10.2 aarch64 Red Hat CodeReady Linux Builder for x86_64 10 x86_64 Red Hat CodeReady Linux Builder for Power, little endian 10 ppc64le Red Hat CodeReady Linux Builder for ARM 64 10 aarch64 Red Hat CodeReady Linux Builder for IBM z Systems 10 s390x Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support 10.2 x86_64 Red Hat CodeReady Linux Builder for Power, little endian - Extended Update Support 10.2 ppc64le Red Hat CodeReady Linux Builder for IBM z Systems - Extended Update Support 10.2 s390x Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support 10.2 aarch64 Red Hat Enterprise Linux for ARM 64 - 4 years of updates 10.2 aarch64 Red Hat Enterprise Linux for IBM z Systems - 4 years of updates 10.2 s390x Red Hat Enterprise Linux for Power, little endian - 4 years of support 10.2 ppc64le Red Hat Enterprise Linux for x86_64 - 4 years of updates 10.2 x86_64 Red Hat Enterprise Linux for x86_64 - Extended Life Cycle 10.2 x86_64 Red Hat Enterprise Linux for ARM 64 - Extended Life Cycle 10.2 aarch64 Red Hat Enterprise Linux for Power, little endian - Extended Life Cycle 10.2 ppc64le Red Hat Enterprise Linux for IBM z Systems - Extended Life Cycle 10.2 s390x Fixes BZ - 2498608 - CVE-2026-15308 python: Python: CPU Denial of Service in HTML parser via repeated unterminated markup declarations CVEs CVE-2026-15308 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 10 SRPM python3.14-3.14.5-1.el10_2.1.src.rpm SHA-256: f859f68dcd8a45d3d95a9dd3aeef1d306b7671e76190647d6f388433163ce307 x86_64 python3.14-3.14.5-1.el10_2.1.x86_64.rpm SHA-256: 2c182f4076471d055c72707e353f4e19b4b6cd61f7875a7f3333fac7b276a751 python3.14-debuginfo-3.14.5-1.el10_2.1.x86_64.rpm SHA-256: cb0f4e7c59f63d177e71463366728bce6afbd83f9d8cb19b5f8bfcd865d13d36 python3.14-debugsource-3.14.5-1.el10_2.1.x86_64.rpm SHA-256: fe8e3f28ca003f1dc6e0e2df89979a7bebdcdec2bb868a98ec4870d91ec3e7c1 python3.14-devel-3.14.5-1.el10_2.1.x86_64.rpm SHA-256: a6338888ec549a24386f313539a2b88d90df9056d80ce0c04be43924e29f9d27 python3.14-libs-3.14.5-1.el10_2.1.x86_64.rpm SHA-256: d8b50e47c58d3e0c30e92d360e9b90269503ff63bdd228d76e270fd6181ef7a3 python3.14-tkinter-3.14.5-1.el10_2.1.x86_64.rpm SHA-256: 8eaa591167b6d08b090c765c56ac6f3ac57468b60ced7c197a6accc064a9c293 Red Hat Enterprise Linux for x86_64 - Extended Update Support 10.2 SRPM python3.14-3.14.5-1.el10_2.1.src.rpm SHA-256: f859f68dcd8a45d3d95a9dd3aeef1d306b7671e76190647d6f388433163ce307 x86_64 python3.14-3.14.5-1.el10_2.1.x86_64.rpm SHA-256: 2c182f4076471d055c72707e353f4e19b4b6cd61f7875a7f3333fac7b276a751 python3.14-debuginfo-3.14.5-1.el10_2.1.x86_64.rpm SHA-256: cb0f4e7c59f63d177e71463366728bce6afbd83f9d8cb19b5f8bfcd865d13d36 python3.14-debugsource-3.14.5-1.el10_2.1.x86_64.rpm SHA-256: fe8e3f28ca003f1dc6e0e2df89979a7bebdcdec2bb868a98ec4870d91ec3e7c1 python3.14-devel-3.14.5-1.el10_2.1.x86_64.rpm SHA-256: a6338888ec549a24386f313539a2b88d90df9056d80ce0c04be43924e29f9d27 python3.14-libs-3.14.5-1.el10_2.1.x86_64.rpm SHA-256: d8b50e47c58d3e0c30e92d360e9b90269503ff63bdd228d76e270fd6181ef7a3 python3.14-tkinter-3.14.5-1.el10_2.1.x86_64.rpm SHA-256: 8eaa591167b6d08b090c765c56ac6f3ac57468b60ced7c197a6accc064a9c293 Red Hat Enterprise Linux for IBM z Systems 10 SRPM python3.14-3.14.5-1.el10_2.1.src.rpm SHA-256: f859f68dcd8a45d3d95a9dd3aeef1d306b7671e76190647d6f388433163ce307 s390x python3.14-3.14.5-1.el10_2.1.s390x.rpm SHA-256: 7264885d82ee8f28d024f5ced796448c21d28aa4afb06964507da17e491dc6f4 python3.14-debuginfo-3.14.5-1.el10_2.1.s390x.rpm SHA-256: e5f99f6e00e6702f66f4ce90a8cf82a560b39b9135ce6adc88c3495aca7bdce0 python3.14-debugsource-3.14.5-1.el10_2.1.s390x.rpm SHA-256: 466626e23a5b84c3ac878812d2990ec6c50fe148737ced7f04dd9ea77c96c86e python3.14-devel-3.14.5-1.el10_2.1.s390x.rpm SHA-256: 4924b53ad94b87d3e160d1742a2be16202bb465cead802d2443758cc4a1a25ec python3.14-libs-3.14.5-1.el10_2.1.s390x.rpm SHA-256: 24c92a46de53ed783c36f7bbb46373a7d5a10eb076dc07698c5f9276f0fa26f6 python3.14-tkinter-3.14.5-1.el10_2.1.s390x.rpm SHA-256: f39a8b55328cbda1313870d1d6f8e2707e1a6c6d4d064c84d3cf6d13998e0304 Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 10.2 SRPM python3.14-3.14.5-1.el10_2.1.src.rpm SHA-256: f859f68dcd8a45d3d95a9dd3aeef1d306b7671e76190647d6f388433163ce307 s390x python3.14-3.14.5-1.el10_2.1.s390x.rpm SHA-256: 7264885d82ee8f28d024f5ced796448c21d28aa4afb06964507da17e491dc6f4 python3.14-debuginfo-3.14.5-1.el10_2.1.s390x.rpm SHA-256: e5f99f6e00e6702f66f4ce90a8cf82a560b39b9135ce6adc88c3495aca7bdce0 python3.14-debugsource-3.14.5-1.el10_2.1.s390x.rpm SHA-256: 466626e23a5b84c3ac878812d2990ec6c50fe148737ced7f04dd9ea77c96c86e python3.14-devel-3.14.5-1.el10_2.1.s390x.rpm SHA-256: 4924b53ad94b87d3e160d1742a2be16202bb465cead802d2443758cc4a1a25ec python3.14-libs-3.14.5-1.el10_2.1.s390x.rpm SHA-256: 24c92a46de53ed783c36f7bbb46373a7d5a10eb076dc07698c5f9276f0fa26f6 python3.14-tkinter-3.14.5-1.el10_2.1.s390x.rpm SHA-256: f39a8b55328cbda1313870d1d6f8e2707e1a6c6d4d064c84d3cf6d13998e0304 Red Hat Enterprise Linux for Power, little endian 10 SRPM python3.14-3.14.5-1.el10_2.1.src.rpm SHA-256: f859f68dcd8a45d3d95a9dd3aeef1d306b7671e76190647d6f388433163ce307 ppc64le python3.14-3.14.5-1.el10_2.1.ppc64le.rpm SHA-256: c0662ad11021d0ecfc9689e0fe76eab098c72cc51fd4088a91af28c7c58aa108 python3.14-debuginfo-3.14.5-1.el10_2.1.ppc64le.rpm SHA-256: b8f86151cafedfb9bf3101388d1ad1a778c7bc3694c204a44a06a84187a498cb python3.14-debugsource-3.14.5-1.el10_2.1.ppc64le.rpm SHA-256: 91847c5c20acb7d9354625e7db8de7cc77d08cc3d3b7643bd70f3aade957a84a python3.14-devel-3.14.5-1.el10_2.1.ppc64le.rpm SHA-256: 1464f557c7c745318b055fddd118af7c8acd60fd6be8d8b49bc5e204b2d6c82c python3.14-libs-3.14.5-1.el10_2.1.ppc64le.rpm SHA-256: c6f4556e27a49fdc15fa139d64f9be68575fae41659af7c7863a9db312ee71dc python3.14-tkinter-3.14.5-1.el10_2.1.ppc64le.rpm SHA-256: 9165cc47717de6bcd16660d89553dae79df6148bdd6db796c509c718b5a3e8c9 Red Hat Enterprise Linux for Power, little endian - Extended Update Support 10.2 SRPM python3.14-3.14.5-1.el10_2.1.src.rpm SHA-256: f859f68dcd8a45d3d95a9dd3aeef1d306b7671e76190647d6f388433163ce307 ppc64le python3.14-3.14.5-1.el10_2.1.ppc64le.rpm SHA-256: c0662ad11021d0ecfc9689e0fe76eab098c72cc51fd4088a91af28c7c58aa108 python3.14-debuginfo-3.14.5-1.el10_2.1.ppc64le.rpm SHA-256: b8f86151cafedfb9bf3101388d1ad1a778c7bc3694c204a44a06a84187a498cb python3.14-debugsource-3.14.5-1.el10_2.1.ppc64le.rpm SHA-256: 91847c5c20acb7d9354625e7db8de7cc77d08cc3d3b7643bd70f3aade957a84a python3.14-devel-3.14.5-1.el10_2.1.ppc64le.rpm SHA-256: 1464f557c7c745318b055fddd118af7c8acd60fd6be8d8b49bc5e204b2d6c82c python3.14-libs-3.14.5-1.el10_2.1.ppc64le.rpm SHA-256: c6f4556e27a49fdc15fa139d64f9be68575fae41659af7c7863a9db312ee71dc python3.14-tkinter-3.14.5-1.el10_2.1.ppc64le.rpm SHA-256: 9165cc47717de6bcd16660d89553dae79df6148bdd6db796c509c718b5a3e8c9 Red Hat Enterprise Linux for ARM 64 10 SRPM python3.14-3.14.5-1.el10_2.1.src.rpm SHA-256: f859f68dcd8a45d3d95a9dd3aeef1d306b7671e76190647d6f388433163ce307 aarch64 python3.14-3.14.5-1.el10_2.1.aarch64.rpm SHA-256: 28ec9b40303cf9b50655b76daeec7fb2d7d20bfcd27eed1f56bbad8574f992e3 python3.14-debuginfo-3.14.5-1.el10_2.1.aarch64.rpm SHA-256: 3409da5e79af580ed16ab76d2b01afe84af7a2ba16f58db5d6bef85617226b74 python3.14-debugsource-3.14.5-1.el10_2.1.aarch64.rpm SHA-256: c3e50cd39a9d1e8c0434d6d12ce2ccba5b43b7959555ccf33c3b74464ce1705a python3.14-devel-3.14.5-1.el10_2.1.aarch64.rpm SHA-256: f698a95254165ef052001886db6a32e891c6896e174a104fa669fecff7c89c6c python3.14-libs-3.14.5-1.el10_2.1.aarch64.rpm SHA-256: 7534c38aabfe35c5a7d9a427c962f532c593d6fe8a787abf53786ea2d4de0fa4 python3.14-tkinter-3.14.5-1.el10_2.1.aarch64.rpm SHA-256: 5ba9b8438f0811db3822f46ae9ce05cbba08a028731644fcedfbaea79901c160 Red Hat Enterprise Linux for ARM 64 - Extended Update Support 10.2 SRPM python3.14-3.14.5-1.el10_2.1.src.rpm SHA