Red Hat Product Errata RHSA-2026:36633 - Security Advisory Issued: 2026-07-08 Updated: 2026-07-08 RHSA-2026:36633 - Security Advisory Overview Updated Packages Synopsis Important: xorg-x11-server-Xwayland 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 xorg-x11-server-Xwayland is now available for Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions. 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 Xwayland is an X server for running X clients under Wayland. Security Fix(es): xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server: stack buffer overflow in font alias resolution due to libXfont2 name length mismatch (CVE-2026-50256) xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server: use-after-free in miSyncDestroyFence() (CVE-2026-50257) xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server: stack buffer overflow in XKB key types due to unchecked shift levels (CVE-2026-50258) xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server: stack buffer overflow in XKB SetMap request via mapWidths indexing (CVE-2026-50259) xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server: use-after-free in FreeCounter() (CVE-2026-50260) xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server: use-after-free in SyncChangeCounter() (CVE-2026-50261) xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server: out-of-bounds read/write in GLX ChangeDrawableAttributes (CVE-2026-50262) xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server: use-after-free information disclosure in CreateSaverWindow() (CVE-2026-50263) xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server: out-of-bounds heap write in DRI2 DRIGetBuffers/DRIGetBuffersWithFormat (CVE-2026-50264) 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 Server - AUS 9.2 x86_64 Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 9.2 ppc64le Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 9.2 x86_64 Red Hat Enterprise Linux for ARM 64 - 4 years of updates 9.2 aarch64 Red Hat Enterprise Linux for IBM z Systems - 4 years of updates 9.2 s390x Red Hat Enterprise Linux for x86_64 - Extended Life Cycle 9.2 x86_64 Red Hat Enterprise Linux for ARM 64 - Extended Life Cycle 9.2 aarch64 Red Hat Enterprise Linux for Power, little endian - Extended Life Cycle 9.2 ppc64le Red Hat Enterprise Linux for IBM z Systems - Extended Life Cycle 9.2 s390x Fixes BZ - 2485380 - CVE-2026-50256 xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server: stack buffer overflow in font alias resolution due to libXfont2 name length mismatch BZ - 2485382 - CVE-2026-50257 xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server: use-after-free in miSyncDestroyFence() BZ - 2485383 - CVE-2026-50258 xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server: stack buffer overflow in XKB key types due to unchecked shift levels BZ - 2485384 - CVE-2026-50259 xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server: stack buffer overflow in XKB SetMap request via mapWidths indexing BZ - 2485385 - CVE-2026-50260 xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server: use-after-free in FreeCounter() BZ - 2485386 - CVE-2026-50261 xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server: use-after-free in SyncChangeCounter() BZ - 2485387 - CVE-2026-50262 xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server: out-of-bounds read/write in GLX ChangeDrawableAttributes BZ - 2485388 - CVE-2026-50263 xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server: use-after-free information disclosure in CreateSaverWindow() BZ - 2485389 - CVE-2026-50264 xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server: out-of-bounds heap write in DRI2 DRIGetBuffers/DRIGetBuffersWithFormat CVEs CVE-2026-50256 CVE-2026-50257 CVE-2026-50258 CVE-2026-50259 CVE-2026-50260 CVE-2026-50261 CVE-2026-50262 CVE-2026-50263 CVE-2026-50264 References https://access.redhat.com/security/updates/classification/#important Note: More recent versions of these packages may be available. Click a package name for more details. Red Hat Enterprise Linux Server - AUS 9.2 SRPM xorg-x11-server-Xwayland-21.1.3-10.el9_2.1.src.rpm SHA-256: ac8ef6643aa475a97cb617eccf228982b017d7fb542a53b48a345457a48d49b1 x86_64 xorg-x11-server-Xwayland-21.1.3-10.el9_2.1.x86_64.rpm SHA-256: af96168287f65d56fbd730444fd1e1981a5dfddf5b999d769f26f71c6a53b56c xorg-x11-server-Xwayland-debuginfo-21.1.3-10.el9_2.1.x86_64.rpm SHA-256: ce44db4110a0cdc5fb110160aca198c5b76e8c4971cf139a8a52f0bdd61ee448 xorg-x11-server-Xwayland-debugsource-21.1.3-10.el9_2.1.x86_64.rpm SHA-256: 2f1356aa22c6e4115e974b3736810f2a8a5c523302270cfc431275812cedd3cc Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 9.2 SRPM xorg-x11-server-Xwayland-21.1.3-10.el9_2.1.src.rpm SHA-256: ac8ef6643aa475a97cb617eccf228982b017d7fb542a53b48a345457a48d49b1 ppc64le xorg-x11-server-Xwayland-21.1.3-10.el9_2.1.ppc64le.rpm SHA-256: 6cf9dd80d3d7d9f8293332d73b7ff1037dac15b8b98eaa59457ca2ba7da49996 xorg-x11-server-Xwayland-debuginfo-21.1.3-10.el9_2.1.ppc64le.rpm SHA-256: 8739713e3086e90b63f598d1b894c99987d5edf3567039562a8aa47e36447719 xorg-x11-server-Xwayland-debugsource-21.1.3-10.el9_2.1.ppc64le.rpm SHA-256: e7857b67e1942bac75cbf76908b4a14545b9ba63007016902cbd4cd7ea0c8cf6 Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 9.2 SRPM xorg-x11-server-Xwayland-21.1.3-10.el9_2.1.src.rpm SHA-256: ac8ef6643aa475a97cb617eccf228982b017d7fb542a53b48a345457a48d49b1 x86_64 xorg-x11-server-Xwayland-21.1.3-10.el9_2.1.x86_64.rpm SHA-256: af96168287f65d56fbd730444fd1e1981a5dfddf5b999d769f26f71c6a53b56c xorg-x11-server-Xwayland-debuginfo-21.1.3-10.el9_2.1.x86_64.rpm SHA-256: ce44db4110a0cdc5fb110160aca198c5b76e8c4971cf139a8a52f0bdd61ee448 xorg-x11-server-Xwayland-debugsource-21.1.3-10.el9_2.1.x86_64.rpm SHA-256: 2f1356aa22c6e4115e974b3736810f2a8a5c523302270cfc431275812cedd3cc Red Hat Enterprise Linux for ARM 64 - 4 years of updates 9.2 SRPM xorg-x11-server-Xwayland-21.1.3-10.el9_2.1.src.rpm SHA-256: ac8ef6643aa475a97cb617eccf228982b017d7fb542a53b48a345457a48d49b1 aarch64 xorg-x11-server-Xwayland-21.1.3-10.el9_2.1.aarch64.rpm SHA-256: 2c4bad399428701768be0ba6ba902d26e5cc3b491dc4b694129260d72676e721 xorg-x11-server-Xwayland-debuginfo-21.1.3-10.el9_2.1.aarch64.rpm SHA-256: 17072d62afba93c1a34073a429ad47254aa19d6fd0aa3a06ede51ca11d772f8f xorg-x11-server-Xwayland-debugsource-21.1.3-10.el9_2.1.aarch64.rpm SHA-256: 3f190a80282df129b830df4030bf259c60e8e9145e44fda9ce61a5f0e3b04802 Red Hat Enterprise Linux for IBM z Systems - 4 years of updates 9.2 SRPM xorg-x11-server-Xwayland-21.1.3-10.el9_2.1.src.rpm SHA-256: ac8ef6643aa475a97cb617eccf228982b017d7fb542a53b48a345457a48d49b1 s390x xorg-x11-server-Xwayland-21.1.3-10.el9_2.1.s390x.rpm SHA-256: 2d7b21048e51efc0bce1f5e4b858363d9e9368ad0a90ceb5ffa7592d1e8c62b2 xorg-x11-server-Xwayland-debuginfo-21.1.3-10.el9_2.1.s390x.rpm SHA-256: ee623bce1faae14cbd7e5a11b8f2c72ce54ffc112820782b04d045837e1f4de3 xorg-x11-server-Xwayland-debugsource-21.1.3-10.el9_2.1.s390x.rpm SHA-256: 3e01dad1cb06a8a9ce83544f003c910d285156dc5f52ee2524c1c804ee660aa0 Red Hat Enterprise Linux for x86_64 - Extended Life Cycle 9.2 SRPM xorg-x11-server-Xwayland-21.1.3-10.el9_2.1.src.rpm SHA-256: ac8ef6643aa475a97cb617eccf228982b017d7fb542a53b48a345457a48d49b1 x86_64 xorg-x11-server-Xwayland-21.1.3-10.el9_2.1.x86_64.rpm SHA-256: af96168287f65d56fbd730444fd1e1981a5dfddf5b999d769f26f71c6a53b56c xorg-x11-server-Xwayland-debuginfo-21.1.3-10.el9_2.1.x86_64.rpm SHA-256: ce44db4110a0cdc5fb110160aca198c5b76e8c4971cf139a8a52f0bdd61ee448 xorg-x11-server-Xwayland-debugsource-21.1.3-10.el9_2.1.x86_64.rpm SHA-256: 2f1356aa22c6e4115e974b3736810f2a8a5c523302270cfc431275812cedd3cc Red Hat Enterprise Linux for ARM 64 - Extended Life Cycle 9.2 SRPM xorg-x11-server-Xwayland-21.1.3-10.el9_2.1.src.rpm SHA-256: ac8ef6643aa475a97cb617eccf228982b017d7fb542a53b48a345457a48d49b1 aarch64 xorg-x11-server-Xwayland-21.1.3-10.el9_2.1.aarch64.rpm SHA-256: 2c4bad399428701768be0ba6ba902d26e5cc3b491dc4b694129260d72676e721 xorg-x11-server-Xwayland-debuginfo-21.1.3-10.el9_2.1.aarch64.rpm SHA-256: 17072d62afba93c1a34073a429ad47254aa19d6fd0aa3a06ede51ca11d772f8f xorg-x11-server-Xwayland-debugsource-21.1.3-10.el9_2.1.aarch64.rpm SHA-256: 3f190a80282df129b830df4030bf259c60e8e9145e44fda9ce61a5f0e3b04802 Red Hat Enterprise Linux for Power, little endian - Extended Life Cycle 9.2 SRPM xorg-x11-server-Xwayland-21.1.3-10.el9_2.1.src.rpm SHA-256: ac8ef6643aa475a97cb617eccf228982b017d7fb542a53b48a345457a48d49b1 ppc64le xorg-x11-server-Xwayland-21.1.3-10.el9_2.1.ppc64le.rpm SHA-256: 6cf9dd80d3d7d9f8293332d73b7ff1037dac15b8b98eaa59457ca2ba7da49996 xorg-x11-server-Xwayland-debuginfo-21.1.3-10.el9_2.1.ppc64le.rpm SHA-256: 8739713e3086e90b63f598d1b894c99987d5edf3567039562a8aa47e36447719 xorg-x11-server-Xwayland-debugsource-21.1.3-10.el9_2.1.ppc64le.rpm SHA-256: e7857b67e1942bac75cbf76908b4a14545b9ba63007016902cbd4cd7ea0c8cf6 Red Hat Enterprise Linux for IBM z Systems - Extended Life Cycle 9.2 SRPM xorg-x11-server-Xwayland-21.1.3-10.el9_2.1.src.rpm SHA-256: ac8ef6643aa475a97cb617eccf228982b017d7fb542a53b48a345457a48d49b1 s390x xorg-x11-server-Xwayland-21.1.3-10.el9_2.1.s390x.rpm SHA-256: 2d7b21048e51efc0bce1f5e4b858363d9e9368ad0a90ceb5ffa7592d1e8c62b2 xorg-x11-serv