Xwayland

A flaw was identified in the X.Org X server’s X Keyboard (Xkb) extension where improper bounds checking in the XkbSetCompatMap() function can cause an unsigned short overflow. If an attacker sends specially crafted input data, the value calculation may overflow, leading to memory corruption or a crash.

Published: 2025-10-30T05:08:32.155Z
Updated: 2026-04-20T13:50:20.474Z

A flaw was discovered in the X.Org X server’s X Keyboard (Xkb) extension when handling client resource cleanup. The software frees certain data structures without properly detaching related resources, leading to a use-after-free condition. This can cause memory corruption or a crash when affected clients disconnect.

Published: 2025-10-30T05:19:40.445Z
Updated: 2026-04-20T13:50:16.428Z

A flaw was found in the X.Org X server and Xwayland when processing X11 Present extension notifications. Improper error handling during notification creation can leave dangling pointers that lead to a use-after-free condition. This can cause memory corruption or a crash, potentially allowing an attacker to execute arbitrary code or cause a denial of service.

Published: 2025-10-30T05:28:48.131Z
Updated: 2026-04-20T13:50:16.096Z

A flaw was found in the RandR extension, where the RRChangeProviderProperty function does not properly validate input. This issue leads to an integer overflow when computing the total size to allocate.

Published: 2025-06-17T15:00:18.145Z
Updated: 2025-12-11T15:34:17.950Z

A flaw was found in the X Record extension. The RecordSanityCheckRegisterClients function does not check for an integer overflow when computing request length, which allows a client to bypass length checks.

Published: 2025-06-17T14:54:49.288Z
Updated: 2025-12-11T15:43:06.188Z

A flaw was found in the X server's request handling. Non-zero 'bytes to ignore' in a client's request can cause the server to skip processing another client's request, potentially leading to a denial of service.

Published: 2025-06-17T14:54:42.646Z
Updated: 2025-12-11T15:43:22.202Z

A flaw was found in the XFIXES extension. The XFixesSetClientDisconnectMode handler does not validate the request length, allowing a client to read unintended memory from previous requests.

Published: 2025-06-17T14:49:49.199Z
Updated: 2025-12-11T15:43:01.939Z

A flaw was found in the Big Requests extension. The request length is multiplied by 4 before checking against the maximum allowed size, potentially causing an integer overflow and bypassing the size check.

Published: 2025-06-17T14:49:49.143Z
Updated: 2025-12-11T15:34:07.129Z

A flaw was found in the X Rendering extension's handling of animated cursors. If a client provides no cursors, the server assumes at least one is present, leading to an out-of-bounds read and potential crash.

Published: 2025-06-17T14:39:39.428Z
Updated: 2025-12-11T15:34:12.649Z

A use-after-free flaw was found in X.Org and Xwayland. When changing an alarm, the values of the change mask are evaluated one after the other, changing the trigger values as requested, and eventually, SyncInitTrigger() is called. If one of the changes triggers an error, the function will return early, not adding the new sync object, possibly causing a use-after-free when the alarm eventually triggers.

Published: 2025-02-25T15:55:36.775Z
Updated: 2026-04-06T12:53:35.517Z

A use-after-free flaw was found in X.Org and Xwayland. When a device is removed while still frozen, the events queued for that device remain while the device is freed. Replaying the events will cause a use-after-free.

Published: 2025-02-25T15:55:20.421Z
Updated: 2026-04-06T12:53:29.954Z

An access to an uninitialized pointer flaw was found in X.Org and Xwayland. The function compCheckRedirect() may fail if it cannot allocate the backing pixmap. In that case, compRedirectWindow() will return a BadAlloc error without validating the window tree marked just before, which leaves the validated data partly initialized and the use of an uninitialized pointer later.

Published: 2025-02-25T15:55:02.964Z
Updated: 2026-04-06T12:53:26.527Z

An out-of-bounds write flaw was found in X.Org and Xwayland. The function GetBarrierDevice() searches for the pointer device based on its device ID and returns the matching value, or supposedly NULL, if no match was found. However, the code will return the last element of the list if no matching device ID is found, which can lead to out-of-bounds memory access.

Published: 2025-02-25T15:54:57.355Z
Updated: 2026-04-06T12:53:25.158Z

A buffer overflow flaw was found in X.Org and Xwayland. If XkbChangeTypesOfKey() is called with a 0 group, it will resize the key symbols table to 0 but leave the key actions unchanged. If the same function is later called with a non-zero value of groups, this will cause a buffer overflow because the key actions are of the wrong size.

Published: 2025-02-25T15:54:48.196Z
Updated: 2026-06-02T03:08:13.330Z

A heap overflow flaw was found in X.Org and Xwayland. The computation of the length in XkbSizeKeySyms() differs from what is written in XkbWriteKeySyms(), which may lead to a heap-based buffer overflow.

Published: 2025-02-25T15:54:23.693Z
Updated: 2026-04-06T12:53:14.993Z

A buffer overflow flaw was found in X.Org and Xwayland. The code in XkbVModMaskText() allocates a fixed-sized buffer on the stack and copies the names of the virtual modifiers to that buffer. The code fails to check the bounds of the buffer and would copy the data regardless of the size.

Published: 2025-02-25T15:54:06.708Z
Updated: 2026-04-06T12:53:14.906Z

A use-after-free flaw was found in X.Org and Xwayland. The root cursor is referenced in the X server as a global variable. If a client frees the root cursor, the internal reference points to freed memory and causes a use-after-free.

Published: 2025-02-25T15:53:51.324Z
Updated: 2026-04-06T12:53:14.958Z

A flaw was found in the X.Org server. The cursor code in both Xephyr and Xwayland uses the wrong type of private at creation. It uses the cursor bits type with the cursor as private, and when initiating the cursor, that overwrites the XSELINUX context.

Published: 2024-01-18T15:40:22.071Z
Updated: 2025-11-20T07:09:01.279Z

A flaw was found in the X.Org server. The GLX PBuffer code does not call the XACE hook when creating the buffer, leaving it unlabeled. When the client issues another request to access that resource (as with a GetGeometry) or when it creates another resource that needs to access that buffer, such as a GC, the XSELINUX code will try to use an object that was never labeled and crash because the SID is NULL.

Published: 2024-01-18T15:40:06.955Z
Updated: 2025-11-20T07:08:59.547Z

An out-of-bounds memory access flaw was found in the X.Org server. This issue can be triggered when a device frozen by a sync grab is reattached to a different master device. This issue may lead to an application crash, local privilege escalation (if the server runs with extended privileges), or remote code execution in SSH X11 forwarding environments.

Published: 2024-02-09T06:29:51.542Z
Updated: 2025-11-06T20:51:57.196Z

A flaw was found in X.Org server. Both DeviceFocusEvent and the XIQueryPointer reply contain a bit for each logical button currently down. Buttons can be arbitrarily mapped to any value up to 255, but the X.Org Server was only allocating space for the device's particular number of buttons, leading to a heap overflow if a bigger value was used.

Published: 2024-01-18T04:31:07.908Z
Updated: 2026-03-19T21:23:24.417Z

A flaw was found in xorg-server. A specially crafted request to RRChangeProviderProperty or RRChangeOutputProperty can trigger an integer overflow which may lead to a disclosure of sensitive information.

Published: 2023-12-13T06:27:41.017Z
Updated: 2025-11-20T07:07:30.871Z

A flaw was found in xorg-server. Querying or changing XKB button actions such as moving from a touchpad to a mouse can result in out-of-bounds memory reads and writes. This may allow local privilege escalation or possible remote code execution in cases where X11 forwarding is involved.

Published: 2023-12-13T06:27:40.758Z
Updated: 2026-03-24T11:27:51.964Z

A use-after-free flaw was found in the xorg-x11-server. An X server crash may occur in a very specific and legacy configuration (a multi-screen setup with multiple protocol screens, also known as Zaphod mode) if the pointer is warped from within a window on one screen to the root window of the other screen and if the original window is destroyed followed by another window being destroyed.

Published: 2023-10-25T19:46:59.432Z
Updated: 2025-11-20T18:06:04.492Z

A out-of-bounds write flaw was found in the xorg-x11-server. This issue occurs due to an incorrect calculation of a buffer offset when copying data stored in the heap in the XIChangeDeviceProperty function in Xi/xiproperty.c and in RRChangeOutputProperty function in randr/rrproperty.c, allowing for possible escalation of privileges or denial of service.

Published: 2023-10-25T19:46:58.494Z
Updated: 2025-11-06T20:51:20.572Z