RHSA-2026:36768: Important: xorg-x11-server security update
Important: xorg-x11-server security update
Other sources
X.Org is an open-source implementation of the X Window System. It provides the basic low-level functionality that full-fledged graphical user interfaces are designed upon.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.
— Red Hat
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
redhat/xorg-x11-serverto a version that resolves this vulnerability.Fixed in 1.20.11-19.el8_8 - Upgrade
Upgrade
redhat/xorg-x11-server-commonto a version that resolves this vulnerability.Fixed in 1.20.11-19.el8_8 - Upgrade
Upgrade
redhat/xorg-x11-server-debuginfoto a version that resolves this vulnerability.Fixed in 1.20.11-19.el8_8 - Upgrade
Upgrade
redhat/xorg-x11-server-debugsourceto a version that resolves this vulnerability.Fixed in 1.20.11-19.el8_8
Event History
Frequently Asked Questions
What is the severity of RHSA-2026:36768?
The severity of RHSA-2026:36768 is classified as high with a score of 7.
How do I fix RHSA-2026:36768?
To fix RHSA-2026:36768, update your xorg-x11-server packages to the latest version provided by Red Hat.
What vulnerabilities are addressed in RHSA-2026:36768?
RHSA-2026:36768 addresses vulnerabilities related to buffer overflow and use after free in xorg-x11-server.
What systems are affected by RHSA-2026:36768?
RHSA-2026:36768 affects Red Hat Enterprise Linux systems that utilize the xorg-x11-server packages.
When was RHSA-2026:36768 published?
RHSA-2026:36768 was published on July 8, 2026.