CVE-2026-50261

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...

X.Org XWayland 缓冲区错误漏洞

The X.Org X Server is an X Window system display server developed by the X.Org Foundation. Xwayland is an open-source communication protocol developed by Xwayland that defines the communication method between the display server and its clients. Both the X.Org X Server and Xwayland have security...

CVE-2026-50262

An out-of-bounds read flaw was found in the X.Org X server and Xwayland in glXDispChangeDrawableAttributes. A wrong size validation check can read a client-controlled number of bytes, exceeding the request buffer, leading to information disclosure. A write path also exists but requires byte-swapp...

CVE-2026-50259

A stack-based buffer overflow flaw was found in the X.Org X server and Xwayland. XkbSetMapChecks declares a fixed-size stack buffer mapWidths256 indexed by key type index. The helper function CheckKeyTypes writes to this buffer at a client-controlled offset, allowing a stack buffer overflow. This...

Important: Red Hat Security Advisory: tigervnc security update

An update for tigervnc is now available for Red Hat Enterprise Linux 6 Extended Lifecycle Support - EXTENSION. 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...

xorg: xwayland: X.Org X server: Information disclosure or Denial of Service via out-of-bounds read in XKB modifier map handling

A flaw was found in the X.Org X server. This vulnerability, an out-of-bounds read, affects the XKB X Keyboard Extension modifier map handling. An attacker with access to the X11 server can exploit this by sending a malformed request, which causes the server to read beyond its intended memory...

xorg: xwayland: X.Org X server: Denial of Service via integer underflow in XKB compatibility map handling

A flaw was found in the X.Org X server. This integer underflow vulnerability, specifically in the XKB compatibility map handling, allows an attacker with local or remote X11 server access to trigger a buffer read overrun. This can lead to memory-safety violations and potentially a denial of servi...

xwayland: xorg: X.Org X server: Information disclosure and denial of service via out-of-bounds read in XKB geometry processing.

A flaw was found in the X.Org X server. This out-of-bounds read vulnerability in the XKB geometry processing, specifically within the CheckSetGeom and XkbAddGeomKeyAlias functions, allows an attacker to read uninitialized or out-of-bounds memory. An attacker with a connection to the X11 server,...

Important: Red Hat Security Advisory: tigervnc security update

An update for tigervnc 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 Vulnerability Scoring...

xorg: xwayland: X.Org X server: Use-after-free vulnerability leads to server crash and potential memory corruption

A flaw was found in the X.Org X server. This use-after-free vulnerability occurs in the XSYNC fence triggering logic, specifically within the miSyncTriggerFence function. An attacker with access to the X11 server can exploit this without user interaction, leading to a server crash and potentially...

xorg: xwayland: X.Org X server: Information disclosure or Denial of Service via out-of-bounds read in XKB modifier map handling

A flaw was found in the X.Org X server. This vulnerability, an out-of-bounds read, affects the XKB X Keyboard Extension modifier map handling. An attacker with access to the X11 server can exploit this by sending a malformed request, which causes the server to read beyond its intended memory...

xwayland: xorg: X.Org X server: Information disclosure and denial of service via out-of-bounds read in XKB geometry processing.

A flaw was found in the X.Org X server. This out-of-bounds read vulnerability in the XKB geometry processing, specifically within the CheckSetGeom and XkbAddGeomKeyAlias functions, allows an attacker to read uninitialized or out-of-bounds memory. An attacker with a connection to the X11 server,...

[SECURITY] Fedora 44 Update: xorg-x11-server-Xwayland-24.1.12-1.fc44

Xwayland is an X server for running X clients under Wayland...

xorg: xwayland: X.Org X server: Information disclosure or Denial of Service via out-of-bounds read in XKB modifier map handling

A flaw was found in the X.Org X server. This vulnerability, an out-of-bounds read, affects the XKB X Keyboard Extension modifier map handling. An attacker with access to the X11 server can exploit this by sending a malformed request, which causes the server to read beyond its intended memory...

xorg: xwayland: X.Org X server: Denial of Service via integer underflow in XKB compatibility map handling

A flaw was found in the X.Org X server. This integer underflow vulnerability, specifically in the XKB compatibility map handling, allows an attacker with local or remote X11 server access to trigger a buffer read overrun. This can lead to memory-safety violations and potentially a denial of servi...

xorg: xwayland: X.Org X server: Use-after-free vulnerability leads to server crash and potential memory corruption

A flaw was found in the X.Org X server. This use-after-free vulnerability occurs in the XSYNC fence triggering logic, specifically within the miSyncTriggerFence function. An attacker with access to the X11 server can exploit this without user interaction, leading to a server crash and potentially...

xorg: xwayland: X.Org X server: Information disclosure or Denial of Service via out-of-bounds read in XKB modifier map handling

A flaw was found in the X.Org X server. This vulnerability, an out-of-bounds read, affects the XKB X Keyboard Extension modifier map handling. An attacker with access to the X11 server can exploit this by sending a malformed request, which causes the server to read beyond its intended memory...

xwayland: xorg: X.Org X server: Information disclosure and denial of service via out-of-bounds read in XKB geometry processing.

A flaw was found in the X.Org X server. This out-of-bounds read vulnerability in the XKB geometry processing, specifically within the CheckSetGeom and XkbAddGeomKeyAlias functions, allows an attacker to read uninitialized or out-of-bounds memory. An attacker with a connection to the X11 server,...

PT-2026-46936

Name of the Vulnerable Software and Affected Versions X.Org X server affected versions not specified Xwayland affected versions not specified rootio-xorg-server versions prior to the fixed versions for Root:Debian:11 Description A stack-based buffer overflow occurs in the X.Org X server and...

xwayland -- Multiple vulnerabilities

X.Org project reports: Multiple issues have been found in the X server and Xwayland implementations published by X.Org for which we are releasing security fixes for in xorg-server-21.1.23 and xwayland-24.1.12...