EUVD-2026-38413

A flaw was found in OpenSSH. A local unprivileged attacker on a Linux client host can hijack client-side X11 forwarding connections. This is possible by pre-binding the preferred abstract X socket name when X11 forwarding is enabled and a local UNIX-domain X socket is used. A successful attack ca...

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...

Astra Linux – Vulnerability in xorg-server

A vulnerability classified as critical was discovered in X.org Server. The vulnerability affects the GetCountedString function in the xkb/xkb.c file. This vulnerability can lead to a buffer overflow. It is recommended that you apply a patch to address this issue. The identifier associated with th...

Astra Linux – Vulnerability in Firefox and Thunderbird

When using X11, text selected by the page using the Selection API is erroneously copied into the primary selection, a temporary storage similar to the clipboard. This bug only affects Firefox on X11. Other systems are unaffected. This vulnerability affects Firefox versions earlier than 120, Firef...

xorg-x11-server-Xwayland security, bug fix, and enhancement update

An update is available for xorg-x11-server-Xwayland. This update affects Rocky Linux 9. A Common Vulnerability Scoring System CVSS base score, which gives a detailed severity rating, is available for each vulnerability from the CVE list Xwayland is an X server for running X clients under Wayland...

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: xorg-x11-server security, bug fix, and enhancement 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-server: xorg-x11-server-Xwayland: xorg-x11-server: stack buffer overflow in font alias resolution du...

[SECURITY] Fedora 43 Update: xorg-x11-server-21.1.23-1.fc43

X.Org X11 X server...

Xorg-x11-server: xorg-x11-server-xwayland: xorg-x11-server: stack buffer overflow in xkb key types due to unchecked shift levels

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Xorg-x11-server: xorg-x11-server-xwayland: xorg-x11-server: use-after-free in syncchangecounter()

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SUSE CVE-2026-50263

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...

EUVD-2026-34817

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...

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...

CVE-2026-50257

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...

[SECURITY] Fedora 44 Update: xorg-x11-server-21.1.23-1.fc44

X.Org X11 X server...

xorg: xwayland: X.Org X server: Information exposure and denial of service via out-of-bounds memory access

A flaw was found in the X.Org X server's XKB key types request validation. A local attacker could send a specially crafted request to the X server, leading to an out-of-bounds memory access vulnerability. This could result in the disclosure of sensitive information or cause the server to crash,...

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,...

RHSA-2026:21712 Red Hat Security Advisory: xorg-x11-server-Xwayland security update

Bulletin has no description...

xorg: xwayland: X.Org X server: Information exposure and denial of service via out-of-bounds memory access

A flaw was found in the X.Org X server's XKB key types request validation. A local attacker could send a specially crafted request to the X server, leading to an out-of-bounds memory access vulnerability. This could result in the disclosure of sensitive information or cause the server to crash,...

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...