xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server: use-after-free in SyncChangeCounter()

A use-after-free flaw was found in the X.Org X server and Xwayland in SyncChangeCounter. A client that sets up multiple SyncCounters can trigger a use-after-free when destroying those counters via a second client connection while changing those counters. This may be used to crash the server, or f...

xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server: use-after-free information disclosure in CreateSaverWindow()

A use-after-free flaw was found in the X.Org X server and Xwayland in CreateSaverWindow. A client can trigger a use-after-free read after changing window attributes and forcing the screen saver, leading to information disclosure...

Important: Red Hat Security Advisory: xorg-x11-server-Xwayland security update

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...

Important: Red Hat Security Advisory: xorg-x11-server security update

An update for xorg-x11-server is now available for Red Hat Enterprise Linux 9. 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 vulnerabilit...

xorg: X11: xserver: X.org: glamor Font Atlas Heap Buffer Overflow

A flaw was found in the glamorfontget function of the xorg-x11-server. This vulnerability, a heap buffer overflow, occurs when the server processes a specially crafted PCF font file where individual glyph metrics exceed the declared maximum bounds. An authenticated X client can exploit this by...

xorg: X11: xserver: X.org: glamor Font Atlas Heap Buffer Overflow

A flaw was found in the glamorfontget function of the xorg-x11-server. This vulnerability, a heap buffer overflow, occurs when the server processes a specially crafted PCF font file where individual glyph metrics exceed the declared maximum bounds. An authenticated X client can exploit this by...

X.org: xorg-x11-server: GLX contextTags Use-After-Free in CommonMakeCurrent()

A flaw was found in the X.org X11 server, specifically within the GLX OpenGL Extension to the X Window System dispatch layer. A remote attacker can exploit this vulnerability by sending a series of crafted X11 requests. This can lead to a use-after-free condition, where the server attempts to wri...

Important: Red Hat Security Advisory: xorg-x11-server-Xwayland security update

An update for xorg-x11-server-Xwayland is now available for Red Hat Enterprise Linux 9. 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...

Important: Red Hat Security Advisory: xorg-x11-server security update

An update for xorg-x11-server is now available for Red Hat Enterprise Linux 8. 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 vulnerabilit...

Important: Red Hat Security Advisory: xorg-x11-server-Xwayland security update

An update for xorg-x11-server-Xwayland 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...

xorg: X11: xserver: X.org: glamor Font Atlas Heap Buffer Overflow

A flaw was found in the glamorfontget function of the xorg-x11-server. This vulnerability, a heap buffer overflow, occurs when the server processes a specially crafted PCF font file where individual glyph metrics exceed the declared maximum bounds. An authenticated X client can exploit this by...

Important: Red Hat Security Advisory: xorg-x11-server-Xwayland security update

An update for xorg-x11-server-Xwayland is now available for Red Hat Enterprise Linux 8. 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...

xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server: out-of-bounds heap write in DRI2 DRIGetBuffers/DRIGetBuffersWithFormat

An out-of-bounds write flaw was found in the X.Org X server and Xwayland in DRIGetBuffers/DRIGetBuffersWithFormat. A client that requests multiple DRI2BufferBackLeft attachments and one DRI2BufferFrontLeft can trigger an out-of-bounds heap write. This may be used to crash the server, or for...

Important: Red Hat Security Advisory: xorg-x11-server-Xwayland security update

An update for xorg-x11-server-Xwayland is now available for Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions and Red Hat Enterprise Linux 8.8 Telecommunications Update Service. Red Hat Product Security has rated this update as having a security impact of Important. A Common...

xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server: use-after-free in miSyncDestroyFence()

A use-after-free flaw was found in the X.Org X server and Xwayland in miSyncDestroyFence. A client that sets up multiple fence triggers can trigger a use-after-free function pointer call. An attacker would connect to the X server to set up a fence and await that fence, then a second X connection...

RHEL 8 : xorg-x11-server-Xwayland (RHSA-2026:38810)

The remote Redhat Enterprise Linux 8 host has a package installed that is affected by multiple vulnerabilities as referenced in the RHSA-2026:38810 advisory. Xwayland is an X server for running X clients under Wayland. Security Fixes: xorg-x11-server: xorg-x11-server-Xwayland: xorg-x11-server:...

RHEL 9 : xorg-x11-server (RHSA-2026:38486)

The remote Redhat Enterprise Linux 9 host has packages installed that are affected by a vulnerability as referenced in the RHSA-2026:38486 advisory. X.Org is an open-source implementation of the X Window System. It provides the basic low-level functionality that full-fledged graphical user...

AlmaLinux 8 : xorg-x11-server-Xwayland (ALSA-2026:38488)

The remote AlmaLinux 8 host has a package installed that is affected by a vulnerability as referenced in the ALSA-2026:38488 advisory. xorg: X11: xserver: X.org: glamor Font Atlas Heap Buffer Overflow CVE-2026-55999 Tenable has extracted the preceding description block directly from the AlmaLinux...

ALSA-2026:38487 Important: xorg-x11-server security update

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 Fixes: xorg: X11: xserver: X.org: glamor Font Atlas Heap Buffer Overflow CVE-2026-55999 For more details about the...

Important: xorg-x11-server security update

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 Fixes: xorg: X11: xserver: X.org: glamor Font Atlas Heap Buffer Overflow CVE-2026-55999 For more details about the...