Red Hat Product Errata RHSA-2026:18693 - Security Advisory Issued: 2026-05-19 Updated: 2026-05-19 RHSA-2026:18693 - Security Advisory Overview Updated Packages Synopsis Moderate: python3.9 security update Type/Severity Security Advisory: Moderate Red Hat Lightspeed patch analysis Identify and remediate systems affected by this advisory. View affected systems Topic An update for python3.9 is now available for Red Hat Enterprise Linux 9. Red Hat Product Security has rated this update as having a security impact of Moderate. 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): cpython: wsgiref.headers.Headers allows header newline injection in Python (CVE-2026-0865) 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. Additional Changes: For detailed information on changes in this release, see the Red Hat Enterprise Linux 9 Release Notes linked from 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 IBM z Systems 9 s390x Red Hat Enterprise Linux for Power, little endian 9 ppc64le Red Hat Enterprise Linux for ARM 64 9 aarch64 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 Fixes BZ - 2431367 - CVE-2026-0865 cpython: wsgiref.headers.Headers allows header newline injection in Python CVEs CVE-2026-0865 References https://access.redhat.com/security/updates/classification/#moderate https://docs.redhat.com/en/documentation/red_hat_enterprise_linux/9/html/9.8_release_notes/index Note: More recent versions of these packages may be available. Click a package name for more details. Red Hat Enterprise Linux for x86_64 9 SRPM python3.9-3.9.25-5.el9_8.src.rpm SHA-256: eb967c4b0c551fc4a1be420f7c541932cb9c6a4cecfdd9a4b638f8bfe7f38cf9 x86_64 python-unversioned-command-3.9.25-5.el9_8.noarch.rpm SHA-256: ac40350cc10163075788d242d243ede34888e8a261c275c5b0fdae701a5ce7be python3-3.9.25-5.el9_8.x86_64.rpm SHA-256: 954a700c9c1a7c27b0971950fdb197a670487a2cfda8d361684c17d8a2bc1d04 python3-devel-3.9.25-5.el9_8.i686.rpm SHA-256: 66e5cf787d6f0b694160c2e47c7203380f9bdb6901fdcc5c544707c8e2a79d7a python3-devel-3.9.25-5.el9_8.x86_64.rpm SHA-256: f7db9826a7ad424a37a84ffb2106d6c71bf63692c86d0a12dc9d605c85ead5c0 python3-libs-3.9.25-5.el9_8.i686.rpm SHA-256: 66c6a6202f1550cadfd905bafc01727a44a7332ce8980adb7fa7cc232a7a0bde python3-libs-3.9.25-5.el9_8.x86_64.rpm SHA-256: cc50921ec56439b8eb146123e7c82ed9d766b30d1a0080d56a1dde88730add21 python3-tkinter-3.9.25-5.el9_8.x86_64.rpm SHA-256: 23cb5048a2a83ef11cb5435d4d723f9c84f5739b008c86641c88300b35790232 python3.9-debuginfo-3.9.25-5.el9_8.i686.rpm SHA-256: eb22e35515f066004ecd3abe7dc24f48b14d3b3c7b066249722e0ed7a1946a15 python3.9-debuginfo-3.9.25-5.el9_8.i686.rpm SHA-256: eb22e35515f066004ecd3abe7dc24f48b14d3b3c7b066249722e0ed7a1946a15 python3.9-debuginfo-3.9.25-5.el9_8.x86_64.rpm SHA-256: 60f13507e555924a16c67fdb6df290c26d269e190745803df3cf58b352b20f65 python3.9-debuginfo-3.9.25-5.el9_8.x86_64.rpm SHA-256: 60f13507e555924a16c67fdb6df290c26d269e190745803df3cf58b352b20f65 python3.9-debugsource-3.9.25-5.el9_8.i686.rpm SHA-256: 5e1978bcd7555b34d6a2f050ba97b4850d23be6a4f5d067f27131a4ed87ded0a python3.9-debugsource-3.9.25-5.el9_8.i686.rpm SHA-256: 5e1978bcd7555b34d6a2f050ba97b4850d23be6a4f5d067f27131a4ed87ded0a python3.9-debugsource-3.9.25-5.el9_8.x86_64.rpm SHA-256: 44fa4609ea2dfe7ede5c993f97cb495884a8de2cd8ea99772b90639cf51de94c python3.9-debugsource-3.9.25-5.el9_8.x86_64.rpm SHA-256: 44fa4609ea2dfe7ede5c993f97cb495884a8de2cd8ea99772b90639cf51de94c Red Hat Enterprise Linux for IBM z Systems 9 SRPM python3.9-3.9.25-5.el9_8.src.rpm SHA-256: eb967c4b0c551fc4a1be420f7c541932cb9c6a4cecfdd9a4b638f8bfe7f38cf9 s390x python-unversioned-command-3.9.25-5.el9_8.noarch.rpm SHA-256: ac40350cc10163075788d242d243ede34888e8a261c275c5b0fdae701a5ce7be python3-3.9.25-5.el9_8.s390x.rpm SHA-256: f5f2928ed2cab05399ba19c33201f6070c3dc5db5f18a6e6b0a7b63cff2dc62f python3-devel-3.9.25-5.el9_8.s390x.rpm SHA-256: 064120630ace697ce501943321d766cac154320a80c4103ed96667b2f810fa5c python3-libs-3.9.25-5.el9_8.s390x.rpm SHA-256: 61493d33efebdeb8edad557732cf8716db84666223091d7c02b4bda5e3d3c023 python3-tkinter-3.9.25-5.el9_8.s390x.rpm SHA-256: a3248adbf6f39f3f8cb0d2bf9944ff66e2ae15f6ca8afb6ea11f80fa5508af0c python3.9-debuginfo-3.9.25-5.el9_8.s390x.rpm SHA-256: d70fe41360ca2b97e1f32aaf673fa615b5f92287c299886557f84ccda07d8b14 python3.9-debuginfo-3.9.25-5.el9_8.s390x.rpm SHA-256: d70fe41360ca2b97e1f32aaf673fa615b5f92287c299886557f84ccda07d8b14 python3.9-debugsource-3.9.25-5.el9_8.s390x.rpm SHA-256: 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python3.9-debugsource-3.9.25-5.el9_8.x86_64.rpm SHA-256: 44fa4609ea2dfe7ede5c993f97cb495884a8de2cd8ea99772b90639cf51de94c Red Hat CodeReady Linux Builder for Power, little endian 9 SRPM ppc64le python3-debug-3.9.25-5.el9_8.ppc64le.rpm SHA-256: 58583b162275d76c267114bf826c39bb1e35d3bb7f4e1f3b3a2fc1ca9e7f7814 python3-idle-3.9.25-5.el9_8.ppc64le.rpm SHA-256: 82860cc01661b3f2d3f3d25a59081ef47cd0bc79fea508f3af48242be99f4a15 python3-test-3.9.25-5.el9_8.ppc64le.rpm SHA-256: 09345b7344e00c3ff2b25ffb1de927f6847f332502d00066d3b902b47c28fd30 python3.9-debuginfo-3.9.25-5.el9_8.ppc64le.rpm SHA-256: 8d2f589e5314c73acc42e3