Red Hat Product Errata RHSA-2026:38810 - Security Advisory Issued: 2026-07-13 Updated: 2026-07-13 RHSA-2026:38810 - 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 8.6 Advanced Mission Critical Update Support and Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On. 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 for x86_64 - Extended Life Cycle Long Life 8.6 x86_64 Red Hat Enterprise Linux Server - AUS 8.6 x86_64 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 for x86_64 - Extended Life Cycle Long Life 8.6 SRPM xorg-x11-server-Xwayland-21.1.3-2.el8_6.7.src.rpm SHA-256: 4f2d4b18dbcc0c8bd57d00d6d4a39630eb2de1a1cee745c8e8af9741fc47c092 x86_64 xorg-x11-server-Xwayland-21.1.3-2.el8_6.7.x86_64.rpm SHA-256: 273375bf55cf482e901beeb6fa1ba1da00a2c5fa2d005b95a90c90e3ff354ab9 xorg-x11-server-Xwayland-debuginfo-21.1.3-2.el8_6.7.x86_64.rpm SHA-256: 92f663b32aa4eb515698bb157b5e5608b96119a057b6534f902322063957a458 xorg-x11-server-Xwayland-debugsource-21.1.3-2.el8_6.7.x86_64.rpm SHA-256: 9a5a9100ecce5766278db8b3a82b9e7a05d2e8e6a913adf2b075d5a83268187f Red Hat Enterprise Linux Server - AUS 8.6 SRPM xorg-x11-server-Xwayland-21.1.3-2.el8_6.7.src.rpm SHA-256: 4f2d4b18dbcc0c8bd57d00d6d4a39630eb2de1a1cee745c8e8af9741fc47c092 x86_64 xorg-x11-server-Xwayland-21.1.3-2.el8_6.7.x86_64.rpm SHA-256: 273375bf55cf482e901beeb6fa1ba1da00a2c5fa2d005b95a90c90e3ff354ab9 xorg-x11-server-Xwayland-debuginfo-21.1.3-2.el8_6.7.x86_64.rpm SHA-256: 92f663b32aa4eb515698bb157b5e5608b96119a057b6534f902322063957a458 xorg-x11-server-Xwayland-debugsource-21.1.3-2.el8_6.7.x86_64.rpm SHA-256: 9a5a9100ecce5766278db8b3a82b9e7a05d2e8e6a913adf2b075d5a83268187f The Red Hat security contact is secalert@redhat.com . More contact details at https://access.redhat.com/security/team/contact/ .