CVE-2026-93517

A heap buffer overflow in handling GLX RenderLarge request where dataBytes exceeds cmdlen in X.org X server before 21.1.25 and XWayland before 24.1.14 that could be be triggered by an authenticated X client could cause crashes or code execution in X server context.

X.Org X11 X server

Security Fix(es):

A flaw was found in the X.Org X Server and XWayland. An error handling issue in the X Keyboard Extension (XKB) geometry processing fails to clear a memory pointer after an allocation failure, leading to a double-free condition during cleanup. A local user can exploit this vulnerability by sending a specially crafted request to the display server. This can cause memory corruption, potentially resulting in a Denial of Service (DoS) or arbitrary code execution with elevated privileges. (From Red Hat.)(CVE-2026-88812)

A flaw was found in xorg-x11-server. A use-after-free vulnerability, where the application accesses memory after it has already been released, occurs in the Present extension because window notification entries are not properly unlinked before cleaning up window resources. An authenticated local X client can exploit this flaw by creating cross-window notifications and subsequently destroying the target window. Successful exploitation primarily results in a Denial of Service (DoS) via an X server crash, and may potentially lead to information disclosure.(CVE-2026-93515)

A flaw was found in xorg-x11-server. A local user can exploit a use-after-free condition—where the software attempts to access memory after it has been freed—by establishing a passive input grab and removing an input device. When subsequent input events are processed, the server dereferences the dangling device pointer. This flaw can lead to arbitrary code execution or a Denial of Service (DoS) via an X server crash.(CVE-2026-93516)

A flaw was found in xorg-x11-server. The GLX (OpenGL Extension to the X Window System) interface fails to verify that incoming data sizes do not exceed allocated buffer limits when handling large rendering requests. An authenticated local client can exploit this vulnerability by sending a specially crafted request, triggering a heap-based buffer overflow. Successful exploitation can result in arbitrary code execution with the privileges of the X server or cause a Denial of Service (DoS) by crashing the application. (From Red Hat.)(CVE-2026-93517)

A flaw was found in xorg-x11-server. Due to an integer truncation issue during memory allocation calculations within the X Keyboard Extension (XKB), the server allocates an undersized buffer when resizing key types. An authenticated local client can exploit this vulnerability by sending specially crafted XKB requests, causing a heap-based buffer overflow. This can result in arbitrary code execution or a denial of service (DoS). (From Red Hat.)(CVE-2026-93518)

Input_constrain_cursor() writes barrier events into a fixed-size buffer without checking bounds. When more than 100 pointer barriers are active, the writes overflow the fixed buffer on the stack or heap. An authenticated X client can trigger this by creating more than 100 pointer barriers (using the XFIXES extension) and then generating pointer motion events (e.g. via XTEST). Both extensions are enabled by default.(CVE-2026-93519)

A flaw was found in xorg-x11-server. In the X Keyboard Extension (XKB), key name memory is allocated with an insufficient buffer size compared to the maximum supported range. An authenticated local client can exploit this flaw by sending requests that modify the keycode range, triggering a heap-based buffer overflow. This vulnerability can lead to arbitrary code execution or cause a Denial of Service (DoS) by crashing the X server.(CVE-2026-93520)

A flaw was found in xorg-x11-server. The X server incorrectly calculates buffer sizes and memory offsets when prepending or appending data to RandR (Resize and Rotate extension) provider properties. A local attacker can exploit this vulnerability by sending specially crafted property update requests, causing memory corruption. This flaw could allow an attacker to escalate privileges or cause a denial of service (DoS) by crashing the X server.(CVE-2026-93521)

A flaw was found in xorg-x11-server. A local…

X.Org X11 X server

Security Fix(es):

A flaw was found in the X.Org X Server and XWayland. An error handling issue in the X Keyboard Extension (XKB) geometry processing fails to clear a memory pointer after an allocation failure, leading to a double-free condition during cleanup. A local user can exploit this vulnerability by sending a specially crafted request to the display server. This can cause memory corruption, potentially resulting in a Denial of Service (DoS) or arbitrary code execution with elevated privileges. (From Red Hat.)(CVE-2026-88812)

A flaw was found in xorg-x11-server. A use-after-free vulnerability, where the application accesses memory after it has already been released, occurs in the Present extension because window notification entries are not properly unlinked before cleaning up window resources. An authenticated local X client can exploit this flaw by creating cross-window notifications and subsequently destroying the target window. Successful exploitation primarily results in a Denial of Service (DoS) via an X server crash, and may potentially lead to information disclosure.(CVE-2026-93515)

A flaw was found in xorg-x11-server. A local user can exploit a use-after-free condition—where the software attempts to access memory after it has been freed—by establishing a passive input grab and removing an input device. When subsequent input events are processed, the server dereferences the dangling device pointer. This flaw can lead to arbitrary code execution or a Denial of Service (DoS) via an X server crash.(CVE-2026-93516)

A flaw was found in xorg-x11-server. The GLX (OpenGL Extension to the X Window System) interface fails to verify that incoming data sizes do not exceed allocated buffer limits when handling large rendering requests. An authenticated local client can exploit this vulnerability by sending a specially crafted request, triggering a heap-based buffer overflow. Successful exploitation can result in arbitrary code execution with the privileges of the X server or cause a Denial of Service (DoS) by crashing the application. (From Red Hat.)(CVE-2026-93517)

A flaw was found in xorg-x11-server. Due to an integer truncation issue during memory allocation calculations within the X Keyboard Extension (XKB), the server allocates an undersized buffer when resizing key types. An authenticated local client can exploit this vulnerability by sending specially crafted XKB requests, causing a heap-based buffer overflow. This can result in arbitrary code execution or a denial of service (DoS). (From Red Hat.)(CVE-2026-93518)

Input_constrain_cursor() writes barrier events into a fixed-size buffer without checking bounds. When more than 100 pointer barriers are active, the writes overflow the fixed buffer on the stack or heap. An authenticated X client can trigger this by creating more than 100 pointer barriers (using the XFIXES extension) and then generating pointer motion events (e.g. via XTEST). Both extensions are enabled by default.(CVE-2026-93519)

A flaw was found in xorg-x11-server. In the X Keyboard Extension (XKB), key name memory is allocated with an insufficient buffer size compared to the maximum supported range. An authenticated local client can exploit this flaw by sending requests that modify the keycode range, triggering a heap-based buffer overflow. This vulnerability can lead to arbitrary code execution or cause a Denial of Service (DoS) by crashing the X server.(CVE-2026-93520)

A flaw was found in xorg-x11-server. The X server incorrectly calculates buffer sizes and memory offsets when prepending or appending data to RandR (Resize and Rotate extension) provider properties. A local attacker can exploit this vulnerability by sending specially crafted property update requests, causing memory corruption. This flaw could allow an attacker to escalate privileges or cause a denial of service (DoS) by crashing the X server.(CVE-2026-93521)

A flaw was found in xorg-x11-server. A local…

X.Org X11 X server

Security Fix(es):

A flaw was found in the X.Org X Server and XWayland. An error handling issue in the X Keyboard Extension (XKB) geometry processing fails to clear a memory pointer after an allocation failure, leading to a double-free condition during cleanup. A local user can exploit this vulnerability by sending a specially crafted request to the display server. This can cause memory corruption, potentially resulting in a Denial of Service (DoS) or arbitrary code execution with elevated privileges. (From Red Hat.)(CVE-2026-88812)

A flaw was found in xorg-x11-server. A use-after-free vulnerability, where the application accesses memory after it has already been released, occurs in the Present extension because window notification entries are not properly unlinked before cleaning up window resources. An authenticated local X client can exploit this flaw by creating cross-window notifications and subsequently destroying the target window. Successful exploitation primarily results in a Denial of Service (DoS) via an X server crash, and may potentially lead to information disclosure.(CVE-2026-93515)

A flaw was found in xorg-x11-server. A local user can exploit a use-after-free condition—where the software attempts to access memory after it has been freed—by establishing a passive input grab and removing an input device. When subsequent input events are processed, the server dereferences the dangling device pointer. This flaw can lead to arbitrary code execution or a Denial of Service (DoS) via an X server crash.(CVE-2026-93516)

A flaw was found in xorg-x11-server. The GLX (OpenGL Extension to the X Window System) interface fails to verify that incoming data sizes do not exceed allocated buffer limits when handling large rendering requests. An authenticated local client can exploit this vulnerability by sending a specially crafted request, triggering a heap-based buffer overflow. Successful exploitation can result in arbitrary code execution with the privileges of the X server or cause a Denial of Service (DoS) by crashing the application. (From Red Hat.)(CVE-2026-93517)

A flaw was found in xorg-x11-server. Due to an integer truncation issue during memory allocation calculations within the X Keyboard Extension (XKB), the server allocates an undersized buffer when resizing key types. An authenticated local client can exploit this vulnerability by sending specially crafted XKB requests, causing a heap-based buffer overflow. This can result in arbitrary code execution or a denial of service (DoS). (From Red Hat.)(CVE-2026-93518)

Input_constrain_cursor() writes barrier events into a fixed-size buffer without checking bounds. When more than 100 pointer barriers are active, the writes overflow the fixed buffer on the stack or heap. An authenticated X client can trigger this by creating more than 100 pointer barriers (using the XFIXES extension) and then generating pointer motion events (e.g. via XTEST). Both extensions are enabled by default.(CVE-2026-93519)

A flaw was found in xorg-x11-server. In the X Keyboard Extension (XKB), key name memory is allocated with an insufficient buffer size compared to the maximum supported range. An authenticated local client can exploit this flaw by sending requests that modify the keycode range, triggering a heap-based buffer overflow. This vulnerability can lead to arbitrary code execution or cause a Denial of Service (DoS) by crashing the X server.(CVE-2026-93520)

A flaw was found in xorg-x11-server. The X server incorrectly calculates buffer sizes and memory offsets when prepending or appending data to RandR (Resize and Rotate extension) provider properties. A local attacker can exploit this vulnerability by sending specially crafted property update requests, causing memory corruption. This flaw could allow an attacker to escalate privileges or cause a denial of service (DoS) by crashing the X server.(CVE-2026-93521)

A flaw was found in xorg-x11-server. A local…

X.Org X11 X server

Security Fix(es):

A flaw was found in the X.Org X Server and XWayland. An error handling issue in the X Keyboard Extension (XKB) geometry processing fails to clear a memory pointer after an allocation failure, leading to a double-free condition during cleanup. A local user can exploit this vulnerability by sending a specially crafted request to the display server. This can cause memory corruption, potentially resulting in a Denial of Service (DoS) or arbitrary code execution with elevated privileges. (From Red Hat.)(CVE-2026-88812)

A flaw was found in xorg-x11-server. A use-after-free vulnerability, where the application accesses memory after it has already been released, occurs in the Present extension because window notification entries are not properly unlinked before cleaning up window resources. An authenticated local X client can exploit this flaw by creating cross-window notifications and subsequently destroying the target window. Successful exploitation primarily results in a Denial of Service (DoS) via an X server crash, and may potentially lead to information disclosure.(CVE-2026-93515)

A flaw was found in xorg-x11-server. A local user can exploit a use-after-free condition—where the software attempts to access memory after it has been freed—by establishing a passive input grab and removing an input device. When subsequent input events are processed, the server dereferences the dangling device pointer. This flaw can lead to arbitrary code execution or a Denial of Service (DoS) via an X server crash.(CVE-2026-93516)

A flaw was found in xorg-x11-server. The GLX (OpenGL Extension to the X Window System) interface fails to verify that incoming data sizes do not exceed allocated buffer limits when handling large rendering requests. An authenticated local client can exploit this vulnerability by sending a specially crafted request, triggering a heap-based buffer overflow. Successful exploitation can result in arbitrary code execution with the privileges of the X server or cause a Denial of Service (DoS) by crashing the application. (From Red Hat.)(CVE-2026-93517)

A flaw was found in xorg-x11-server. Due to an integer truncation issue during memory allocation calculations within the X Keyboard Extension (XKB), the server allocates an undersized buffer when resizing key types. An authenticated local client can exploit this vulnerability by sending specially crafted XKB requests, causing a heap-based buffer overflow. This can result in arbitrary code execution or a denial of service (DoS). (From Red Hat.)(CVE-2026-93518)

Input_constrain_cursor() writes barrier events into a fixed-size buffer without checking bounds. When more than 100 pointer barriers are active, the writes overflow the fixed buffer on the stack or heap. An authenticated X client can trigger this by creating more than 100 pointer barriers (using the XFIXES extension) and then generating pointer motion events (e.g. via XTEST). Both extensions are enabled by default.(CVE-2026-93519)

A flaw was found in xorg-x11-server. In the X Keyboard Extension (XKB), key name memory is allocated with an insufficient buffer size compared to the maximum supported range. An authenticated local client can exploit this flaw by sending requests that modify the keycode range, triggering a heap-based buffer overflow. This vulnerability can lead to arbitrary code execution or cause a Denial of Service (DoS) by crashing the X server.(CVE-2026-93520)

A flaw was found in xorg-x11-server. The X server incorrectly calculates buffer sizes and memory offsets when prepending or appending data to RandR (Resize and Rotate extension) provider properties. A local attacker can exploit this vulnerability by sending specially crafted property update requests, causing memory corruption. This flaw could allow an attacker to escalate privileges or cause a denial of service (DoS) by crashing the X server.(CVE-2026-93521)

A flaw was found in xorg-x11-server. A local…

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: Arbitrary code execution via use-after-free in passive grab handling (CVE-2026-93516)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via GLX RenderLarge heap-based buffer overflow (CVE-2026-93517)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via integer truncation during keyboard mapping resize (CVE-2026-93518)

• xorg-x11-server: xorg-x11-server: Arbitrary code execution via buffer overflow in input_constrain_cursor() (CVE-2026-93519)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via out-of-bounds write in XKB keycode handling (CVE-2026-93520)

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.

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

Security Fix(es):

• xorg-x11-server: xorg-x11-server: Arbitrary code execution via use-after-free in passive grab handling (CVE-2026-93516)

• xorg-x11-server: xorg-x11-server: Privilege escalation via crafted RandR provider property requests (CVE-2026-93521)

• xorg-x11-server: xwayland: xorg-x11-server: Arbitrary code execution via double-free in XKB geometry handling (CVE-2026-88812)

• xorg-x11-server: xorg-x11-server: Out-of-bounds write via unvalidated modifier in ProcXIPassiveUngrabDevice (CVE-2026-93523)

• xorg-x11-server: glamor: size tmp_bits buffer for source coordinate range in upload_boxes (CVE-2026-93522)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via GLX RenderLarge heap-based buffer overflow (CVE-2026-93517)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via integer truncation during keyboard mapping resize (CVE-2026-93518)

• xorg-x11-server: xorg-x11-server: Arbitrary code execution via buffer overflow in input_constrain_cursor() (CVE-2026-93519)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via out-of-bounds write in XKB keycode handling (CVE-2026-93520)

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.

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

Security Fix(es):

• xorg-x11-server: xorg-x11-server: Arbitrary code execution via use-after-free in passive grab handling (CVE-2026-93516)

• xorg-x11-server: xorg-x11-server: Privilege escalation via crafted RandR provider property requests (CVE-2026-93521)

• xorg-x11-server: xwayland: xorg-x11-server: Arbitrary code execution via double-free in XKB geometry handling (CVE-2026-88812)

• xorg-x11-server: xorg-x11-server: Out-of-bounds write via unvalidated modifier in ProcXIPassiveUngrabDevice (CVE-2026-93523)

• xorg-x11-server: glamor: size tmp_bits buffer for source coordinate range in upload_boxes (CVE-2026-93522)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via GLX RenderLarge heap-based buffer overflow (CVE-2026-93517)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via integer truncation during keyboard mapping resize (CVE-2026-93518)

• xorg-x11-server: xorg-x11-server: Arbitrary code execution via buffer overflow in input_constrain_cursor() (CVE-2026-93519)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via out-of-bounds write in XKB keycode handling (CVE-2026-93520)

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.

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

Security Fix(es):

• xorg-x11-server: xorg-x11-server: Arbitrary code execution via use-after-free in passive grab handling (CVE-2026-93516)

• xorg-x11-server: xorg-x11-server: Privilege escalation via crafted RandR provider property requests (CVE-2026-93521)

• xorg-x11-server: xwayland: xorg-x11-server: Arbitrary code execution via double-free in XKB geometry handling (CVE-2026-88812)

• xorg-x11-server: xorg-x11-server: Out-of-bounds write via unvalidated modifier in ProcXIPassiveUngrabDevice (CVE-2026-93523)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via GLX RenderLarge heap-based buffer overflow (CVE-2026-93517)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via integer truncation during keyboard mapping resize (CVE-2026-93518)

• xorg-x11-server: xorg-x11-server: Arbitrary code execution via buffer overflow in input_constrain_cursor() (CVE-2026-93519)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via out-of-bounds write in XKB keycode handling (CVE-2026-93520)

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.

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: Arbitrary code execution via use-after-free in passive grab handling (CVE-2026-93516)

• xorg-x11-server: xorg-x11-server: Privilege escalation via crafted RandR provider property requests (CVE-2026-93521)

• xorg-x11-server: xwayland: xorg-x11-server: Arbitrary code execution via double-free in XKB geometry handling (CVE-2026-88812)

• xorg-x11-server: xorg-x11-server: Out-of-bounds write via unvalidated modifier in ProcXIPassiveUngrabDevice (CVE-2026-93523)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via GLX RenderLarge heap-based buffer overflow (CVE-2026-93517)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via integer truncation during keyboard mapping resize (CVE-2026-93518)

• xorg-x11-server: xorg-x11-server: Arbitrary code execution via buffer overflow in input_constrain_cursor() (CVE-2026-93519)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via out-of-bounds write in XKB keycode handling (CVE-2026-93520)

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.

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

Security Fix(es):

• xorg-x11-server: xorg-x11-server: Arbitrary code execution via use-after-free in passive grab handling (CVE-2026-93516)

• xorg-x11-server: xorg-x11-server: Privilege escalation via crafted RandR provider property requests (CVE-2026-93521)

• xorg-x11-server: xwayland: xorg-x11-server: Arbitrary code execution via double-free in XKB geometry handling (CVE-2026-88812)

• xorg-x11-server: xorg-x11-server: Out-of-bounds write via unvalidated modifier in ProcXIPassiveUngrabDevice (CVE-2026-93523)

• xorg-x11-server: glamor: size tmp_bits buffer for source coordinate range in upload_boxes (CVE-2026-93522)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via GLX RenderLarge heap-based buffer overflow (CVE-2026-93517)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via integer truncation during keyboard mapping resize (CVE-2026-93518)

• xorg-x11-server: xorg-x11-server: Arbitrary code execution via buffer overflow in input_constrain_cursor() (CVE-2026-93519)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via out-of-bounds write in XKB keycode handling (CVE-2026-93520)

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.

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: Arbitrary code execution via use-after-free in passive grab handling (CVE-2026-93516)

• xorg-x11-server: xorg-x11-server: Privilege escalation via crafted RandR provider property requests (CVE-2026-93521)

• xorg-x11-server: xwayland: xorg-x11-server: Arbitrary code execution via double-free in XKB geometry handling (CVE-2026-88812)

• xorg-x11-server: xorg-x11-server: Out-of-bounds write via unvalidated modifier in ProcXIPassiveUngrabDevice (CVE-2026-93523)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via GLX RenderLarge heap-based buffer overflow (CVE-2026-93517)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via integer truncation during keyboard mapping resize (CVE-2026-93518)

• xorg-x11-server: xorg-x11-server: Arbitrary code execution via buffer overflow in input_constrain_cursor() (CVE-2026-93519)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via out-of-bounds write in XKB keycode handling (CVE-2026-93520)

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.

Virtual Network Computing (VNC) is a remote display system which allows users to view a computing desktop environment not only on the machine where it is running, but from anywhere on the Internet and from a wide variety of machine architectures. TigerVNC is a suite of VNC servers and clients.

Security Fix(es):

• xorg-x11-server: xorg-x11-server: Arbitrary code execution via use-after-free in passive grab handling (CVE-2026-93516)

• xorg-x11-server: xorg-x11-server: Privilege escalation via crafted RandR provider property requests (CVE-2026-93521)

• xorg-x11-server: xwayland: xorg-x11-server: Arbitrary code execution via double-free in XKB geometry handling (CVE-2026-88812)

• xorg-x11-server: xorg-x11-server: Out-of-bounds write via unvalidated modifier in ProcXIPassiveUngrabDevice (CVE-2026-93523)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via GLX RenderLarge heap-based buffer overflow (CVE-2026-93517)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via integer truncation during keyboard mapping resize (CVE-2026-93518)

• xorg-x11-server: xorg-x11-server: Arbitrary code execution via buffer overflow in input_constrain_cursor() (CVE-2026-93519)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via out-of-bounds write in XKB keycode handling (CVE-2026-93520)

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.

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

Security Fix(es):

• xorg-x11-server: xorg-x11-server: Arbitrary code execution via use-after-free in passive grab handling (CVE-2026-93516)

• xorg-x11-server: xorg-x11-server: Privilege escalation via crafted RandR provider property requests (CVE-2026-93521)

• xorg-x11-server: xwayland: xorg-x11-server: Arbitrary code execution via double-free in XKB geometry handling (CVE-2026-88812)

• xorg-x11-server: xorg-x11-server: Out-of-bounds write via unvalidated modifier in ProcXIPassiveUngrabDevice (CVE-2026-93523)

• xorg-x11-server: glamor: size tmp_bits buffer for source coordinate range in upload_boxes (CVE-2026-93522)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via GLX RenderLarge heap-based buffer overflow (CVE-2026-93517)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via integer truncation during keyboard mapping resize (CVE-2026-93518)

• xorg-x11-server: xorg-x11-server: Arbitrary code execution via buffer overflow in input_constrain_cursor() (CVE-2026-93519)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via out-of-bounds write in XKB keycode handling (CVE-2026-93520)

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.

Virtual Network Computing (VNC) is a remote display system which allows users to view a computing desktop environment not only on the machine where it is running, but from anywhere on the Internet and from a wide variety of machine architectures. TigerVNC is a suite of VNC servers and clients.

Security Fix(es):

• xorg-x11-server: xorg-x11-server: Arbitrary code execution via use-after-free in passive grab handling (CVE-2026-93516)

• xorg-x11-server: xorg-x11-server: Privilege escalation via crafted RandR provider property requests (CVE-2026-93521)

• xorg-x11-server: xwayland: xorg-x11-server: Arbitrary code execution via double-free in XKB geometry handling (CVE-2026-88812)

• xorg-x11-server: xorg-x11-server: Out-of-bounds write via unvalidated modifier in ProcXIPassiveUngrabDevice (CVE-2026-93523)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via GLX RenderLarge heap-based buffer overflow (CVE-2026-93517)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via integer truncation during keyboard mapping resize (CVE-2026-93518)

• xorg-x11-server: xorg-x11-server: Arbitrary code execution via buffer overflow in input_constrain_cursor() (CVE-2026-93519)

• xorg-x11-server: xorg-x11-server: arbitrary code execution via out-of-bounds write in XKB keycode handling (CVE-2026-93520)

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.

A heap buffer overflow in handling GLX RenderLarge request where dataBytes exceeds cmdlen in X.org X server before 21.1.25 and XWayland before 24.1.14 that could be be triggered by an authenticated X client could cause crashes or code execution in X server context.

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: Arbitrary code execution via use-after-free in passive grab handling (CVE-2026-93516)
• xorg-x11-server: xorg-x11-server: arbitrary code execution via GLX RenderLarge heap-based buffer overflow (CVE-2026-93517)
• xorg-x11-server: xorg-x11-server: arbitrary code execution via integer truncation during keyboard mapping resize (CVE-2026-93518)
• xorg-x11-server: xorg-x11-server: Arbitrary code execution via buffer overflow in input_constrain_cursor() (CVE-2026-93519)
• xorg-x11-server: xorg-x11-server: arbitrary code execution via out-of-bounds write in XKB keycode handling (CVE-2026-93520)

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.

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

Security Fix(es):

• xorg-x11-server: xorg-x11-server: Arbitrary code execution via use-after-free in passive grab handling (CVE-2026-93516)
• xorg-x11-server: xorg-x11-server: Privilege escalation via crafted RandR provider property requests (CVE-2026-93521)
• xorg-x11-server: xwayland: xorg-x11-server: Arbitrary code execution via double-free in XKB geometry handling (CVE-2026-88812)
• xorg-x11-server: xorg-x11-server: Out-of-bounds write via unvalidated modifier in ProcXIPassiveUngrabDevice (CVE-2026-93523)
• xorg-x11-server: glamor: size tmp_bits buffer for source coordinate range in upload_boxes (CVE-2026-93522)
• xorg-x11-server: xorg-x11-server: arbitrary code execution via GLX RenderLarge heap-based buffer overflow (CVE-2026-93517)
• xorg-x11-server: xorg-x11-server: arbitrary code execution via integer truncation during keyboard mapping resize (CVE-2026-93518)
• xorg-x11-server: xorg-x11-server: Arbitrary code execution via buffer overflow in input_constrain_cursor() (CVE-2026-93519)
• xorg-x11-server: xorg-x11-server: arbitrary code execution via out-of-bounds write in XKB keycode handling (CVE-2026-93520)

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.

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

Security Fix(es):

• xorg-x11-server: xorg-x11-server: Arbitrary code execution via use-after-free in passive grab handling (CVE-2026-93516)
• xorg-x11-server: xorg-x11-server: Privilege escalation via crafted RandR provider property requests (CVE-2026-93521)
• xorg-x11-server: xwayland: xorg-x11-server: Arbitrary code execution via double-free in XKB geometry handling (CVE-2026-88812)
• xorg-x11-server: xorg-x11-server: Out-of-bounds write via unvalidated modifier in ProcXIPassiveUngrabDevice (CVE-2026-93523)
• xorg-x11-server: glamor: size tmp_bits buffer for source coordinate range in upload_boxes (CVE-2026-93522)
• xorg-x11-server: xorg-x11-server: arbitrary code execution via GLX RenderLarge heap-based buffer overflow (CVE-2026-93517)
• xorg-x11-server: xorg-x11-server: arbitrary code execution via integer truncation during keyboard mapping resize (CVE-2026-93518)
• xorg-x11-server: xorg-x11-server: Arbitrary code execution via buffer overflow in input_constrain_cursor() (CVE-2026-93519)
• xorg-x11-server: xorg-x11-server: arbitrary code execution via out-of-bounds write in XKB keycode handling (CVE-2026-93520)

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.

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

Security Fix(es):

• xorg-x11-server: xorg-x11-server: Arbitrary code execution via use-after-free in passive grab handling (CVE-2026-93516)
• xorg-x11-server: xorg-x11-server: Privilege escalation via crafted RandR provider property requests (CVE-2026-93521)
• xorg-x11-server: xwayland: xorg-x11-server: Arbitrary code execution via double-free in XKB geometry handling (CVE-2026-88812)
• xorg-x11-server: xorg-x11-server: Out-of-bounds write via unvalidated modifier in ProcXIPassiveUngrabDevice (CVE-2026-93523)
• xorg-x11-server: xorg-x11-server: arbitrary code execution via GLX RenderLarge heap-based buffer overflow (CVE-2026-93517)
• xorg-x11-server: xorg-x11-server: arbitrary code execution via integer truncation during keyboard mapping resize (CVE-2026-93518)
• xorg-x11-server: xorg-x11-server: Arbitrary code execution via buffer overflow in input_constrain_cursor() (CVE-2026-93519)
• xorg-x11-server: xorg-x11-server: arbitrary code execution via out-of-bounds write in XKB keycode handling (CVE-2026-93520)

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.

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: Arbitrary code execution via use-after-free in passive grab handling (CVE-2026-93516)
• xorg-x11-server: xorg-x11-server: Privilege escalation via crafted RandR provider property requests (CVE-2026-93521)
• xorg-x11-server: xwayland: xorg-x11-server: Arbitrary code execution via double-free in XKB geometry handling (CVE-2026-88812)
• xorg-x11-server: xorg-x11-server: Out-of-bounds write via unvalidated modifier in ProcXIPassiveUngrabDevice (CVE-2026-93523)
• xorg-x11-server: xorg-x11-server: arbitrary code execution via GLX RenderLarge heap-based buffer overflow (CVE-2026-93517)
• xorg-x11-server: xorg-x11-server: arbitrary code execution via integer truncation during keyboard mapping resize (CVE-2026-93518)
• xorg-x11-server: xorg-x11-server: Arbitrary code execution via buffer overflow in input_constrain_cursor() (CVE-2026-93519)
• xorg-x11-server: xorg-x11-server: arbitrary code execution via out-of-bounds write in XKB keycode handling (CVE-2026-93520)

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.

Virtual Network Computing (VNC) is a remote display system which allows users to view a computing desktop environment not only on the machine where it is running, but from anywhere on the Internet and from a wide variety of machine architectures. TigerVNC is a suite of VNC servers and clients.

Security Fix(es):

• xorg-x11-server: xorg-x11-server: Arbitrary code execution via use-after-free in passive grab handling (CVE-2026-93516)
• xorg-x11-server: xorg-x11-server: Privilege escalation via crafted RandR provider property requests (CVE-2026-93521)
• xorg-x11-server: xwayland: xorg-x11-server: Arbitrary code execution via double-free in XKB geometry handling (CVE-2026-88812)
• xorg-x11-server: xorg-x11-server: Out-of-bounds write via unvalidated modifier in ProcXIPassiveUngrabDevice (CVE-2026-93523)
• xorg-x11-server: xorg-x11-server: arbitrary code execution via GLX RenderLarge heap-based buffer overflow (CVE-2026-93517)
• xorg-x11-server: xorg-x11-server: arbitrary code execution via integer truncation during keyboard mapping resize (CVE-2026-93518)
• xorg-x11-server: xorg-x11-server: Arbitrary code execution via buffer overflow in input_constrain_cursor() (CVE-2026-93519)
• xorg-x11-server: xorg-x11-server: arbitrary code execution via out-of-bounds write in XKB keycode handling (CVE-2026-93520)

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.

A heap buffer overflow in handling GLX RenderLarge request where dataBytes exceeds cmdlen in X.org X server before 21.1.25 and XWayland before 24.1.14 that could be be triggered by an authenticated X client could cause crashes or code execution in X server context.

A heap buffer overflow in handling GLX RenderLarge request where dataBytes exceeds cmdlen in X.org X server before 21.1.25 and XWayland before 24.1.14 that could be be triggered by an authenticated X client could cause crashes or code execution in X server context.

A heap buffer overflow in handling GLX RenderLarge request where dataBytes exceeds cmdlen in X.org X server before 21.1.25 and XWayland before 24.1.14 that could be be triggered by an authenticated X client could cause crashes or code execution in X server context.

• CVE-2026-88812: Use-after-free/double free in XKB _CheckSetDoodad: doodad text pointer left dangling after free when reading the font string fails
• CVE-2026-93516: Use-after-free in DIX: passive grabs keep dangling pointers to a removed input device (grab->device / modifierDevice)
• CVE-2026-93517: Out-of-bounds read in GLX RenderLarge: dataBytes of the first request not validated against the request length
• CVE-2026-93518: Heap buffer overflow in XKB key resize: 16-bit size_syms/num_syms/size_acts/num_acts truncate computed sizes, undersizing allocations
• CVE-2026-93519: Out-of-bounds write in XInput barrier handling: input_constrain_cursor writes barrier events without a bounds check
• CVE-2026-93521: Heap memory corruption in RandR RRChangeProviderProperty PrependMode due to wrong size and offset when shifting old data
• CVE-2026-93522: Heap buffer overflow in glamor_upload_boxes: tmp_bits sized from pixmap height, not the source coordinate range
• CVE-2026-93523: Out-of-bounds access in XInput ProcXIPassiveUngrabDevice: client-supplied modifier values are not validated

• CVE-2026-93517: GLX RenderLarge copied client dataBytes into a buffer sized by the smaller embedded cmdlen, allowing a heap buffer overflow
• CVE-2026-93518: XKB size_syms/num_syms/size_acts/num_acts were 16-bit, so resize computations truncated and caused undersized allocations and heap overflow
• CVE-2026-93519: Crossing many pointer barriers at once wrote barrier events past the end of the fixed-size input event buffer (heap overflow)

XKB SetGeometry TextDoodad Double Free. (CVE-2026-88812) Present Extension Cross-Window Notify Use-After-Free. (CVE-2026-93515) XInput Passive Grab modifierDevice Use-After-Free. (CVE-2026-93516) GLX RenderLarge Heap Buffer Overflow. (CVE-2026-93517) XKB ResizeKeyType Numeric Truncation. (CVE-2026-93518) XFixes Pointer Barrier Event List Buffer Overflow. (CVE-2026-93519) XKB ChangeKeycodeRange Heap Out-of-Bounds Write. (CVE-2026-93520) RandR ChangeProviderProperty Heap Buffer Overflow. (CVE-2026-93521) Glamor CopyArea CPU-FBO Heap Buffer Overflow. (CVE-2026-93522) XInput2 PassiveUngrabDevice Modifier Out-of-Bounds Write. (CVE-2026-93523) XKB SetMap Key Width/Action Count Desync Out-Of-Bounds Read. (CVE-2026-93524) GestureBuildSprite Use-After-Free. (CVE-2026-93536)