X Server vulnerabilities
40 known vulnerabilities in X Server from X.Org. 40 are rated high or critical. Each entry lists the affected versions and the release that fixes it, where the vendor has published one.
Latest first
- 7.8 High severity
xorg-x11-server: Use After Free
Local attackers with a X connection able to provide GLX commit to the X server xorg-server before 21.2.24 and xwayland before 24.1.13 could cause a Heap Use After Free, due to CommonMakeCurrent() pointing into potentially reallocated memory.
- 7.8 High severity
xorg-server: Heap-based Buffer Overflow
Local attackers with a X connection able to provide PCX fonts to the X server xorg-server before 21.2.24 and xwayland before 24.1.13 could cause a heap buffer overflow via SetFont due to missing glyph boundary checks.
- 7.8 High severity
Red Hat Enterprise Linux 10: Out-of-bounds Write
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 u
- 7.8 High severity
Red Hat Enterprise Linux 10: Use After Free
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. Thi
- 7.8 High severity
Red Hat Enterprise Linux 10: Use After Free
A use-after-free flaw was found in the X.Org X server and Xwayland in FreeCounter(). A client that sets up multiple SyncCounters and awaits on those triggers can trigger a use-after-free when destroying those counters via a second client connection. This may b
- 7.8 High severity
Red Hat Enterprise Linux 10: Stack-based Buffer Overflow
A stack-based buffer overflow flaw was found in the X.Org X server and Xwayland. _XkbSetMapChecks() declares a fixed-size stack buffer mapWidths[256] indexed by key type index. The helper function CheckKeyTypes() writes to this buffer at a client-controlled of
- 7.8 High severity
Red Hat Enterprise Linux 10: Stack-based Buffer Overflow
A stack-based buffer overflow flaw was found in the X.Org X server and Xwayland. The X server has multiple stack buffers sized XkbMaxShiftLevel * XkbNumKbdGroups but CheckKeyTypes() does not verify or clamp non-canonical key types to XkbMaxShiftLevel. A client
- 7.8 High severity
Red Hat Enterprise Linux 10: Use After Free
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
- 7.8 High severity
Red Hat Enterprise Linux 10: Stack-based Buffer Overflow
A stack-based buffer overflow flaw was found in the X.Org X server and Xwayland. A mismatch between the X server and the libXfont2 library's maximum font name length can cause a stack buffer overflow during font alias resolution. The server allocates a 256 byt
- 9.1 Critical severity
Red Hat Enterprise Linux 10.0 Extended Update…: Buffer Access with Incorrect Length Value
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
- 9.1 Critical severity
Red Hat Enterprise Linux 10.0 Extended Update…: Out-of-bounds Read
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 atta
- 7.3 High severity
Xwayland: Use After Free
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 memor
- 7.3 High severity
Xwayland: Integer Overflow or Wraparound
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 overflo
- 7.7 High severity
X server: Improper Resource Locking
In X.Org X server 20.11 through 21.1.16, when a client application uses easystroke for mouse gestures, the main thread modifies various data structures used by the input thread without acquiring a lock, aka a race condition. In particular, AttachDevice in dix/
- 7.8 High severity
Red Hat Enterprise Linux 10: Use After Free
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 trigger
- 7.8 High severity
Red Hat Enterprise Linux 10: Use After Free
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.
- 7.8 High severity
Red Hat Enterprise Linux 10: Access of Uninitialized Pointer
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 m
- 7.8 High severity
Red Hat Enterprise Linux 10: Out-of-bounds Write
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 las
- 7.8 High severity
Red Hat Enterprise Linux 10: Improper Restriction of Operations within the Bounds of a Memory Buffer
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
- 7.8 High severity
Red Hat Enterprise Linux 10: Out-of-bounds Write
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.
- 7.8 High severity
Red Hat Enterprise Linux 10: Out-of-bounds Write
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
- 7.8 High severity
Red Hat Enterprise Linux 10: Use After Free
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.
- 7.8 High severity
Red Hat Enterprise Linux 6 Extended Lifecycle…: Out-of-bounds Write
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 serve
- 7.8 High severity
Red Hat Enterprise Linux 7: Out-of-bounds Write
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.
- 9.8 Critical severity
Red Hat Enterprise Linux 6 Extended Lifecycle…: Out-of-bounds Write
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
- 7.5 High severity
Red Hat Enterprise Linux 6 Extended Lifecycle…: Integer Overflow or Wraparound
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.
- 7.8 High severity
Red Hat Enterprise Linux 6 Extended Lifecycle…: Out-of-bounds Read
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 X
- 7.0 High severity
Red Hat Enterprise Linux 9: Use After Free
A use-after-free flaw was found in xorg-x11-server-Xvfb. This issue occurs in Xvfb with 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 a screen 1 to a scr
- 7.8 High severity
Red Hat Enterprise Linux 6 Extended Lifecycle…: Out-of-bounds Write
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 funct
- 7.8 High severity
xorg-server: Use After Free
A flaw was found in X.Org Server Overlay Window. A Use-After-Free may lead to local privilege escalation. If a client explicitly destroys the compositor overlay window (aka COW), the Xserver would leave a dangling pointer to that window in the CompScreen struc
- 7.8 High severity
xorg-x11-server: Use After Free
A vulnerability was found in X.Org. This issue occurs due to a dangling pointer in DeepCopyPointerClasses that can be exploited by ProcXkbSetDeviceInfo() and ProcXkbGetDeviceInfo() to read and write into freed memory. This can lead to local privilege elevation
- 7.8 High severity
xorg-x11-server: Use After Free
A vulnerability was found in X.Org. This security flaw occurs because the XkbCopyNames function left a dangling pointer to freed memory, resulting in out-of-bounds memory access on subsequent XkbGetKbdByName requests.. This issue can lead to local privileges e
- 8.8 High severity
xorg-x11-server: Out-of-bounds Read
A vulnerability was found in X.Org. This security flaw occurs because the handler for the XIChangeProperty request has a length-validation issues, resulting in out-of-bounds memory reads and potential information disclosure. This issue can lead to local privil
- 8.8 High severity
xorg-x11-server: Use After Free
A vulnerability was found in X.Org. This security flaw occurs because the handler for the ScreenSaverSetAttributes request may write to memory after it has been freed. This issue can lead to local privileges elevation on systems where the X server is running p
- 8.8 High severity
xorg-x11-server: Use After Free
A vulnerability was found in X.Org. This security flaw occurs because the handler for the XvdiSelectVideoNotify request may write to memory after it has been freed. This issue can lead to local privileges elevation on systems where the X se
- 8.8 High severity
xorg-x11-server: Out-of-bounds Write
A vulnerability was found in X.Org. This security flaw occurs because the handler for the XIPassiveUngrab request accesses out-of-bounds memory when invoked with a high keycode or button code. This issue can lead to local privileges elevation on systems where
- 8.8 High severity
xorg-x11-server: Out-of-bounds Write
A vulnerability was found in X.Org. This security flaw occurs becuase the swap handler for the XTestFakeInput request of the XTest extension may corrupt the stack if GenericEvents with lengths larger than 32 bytes are sent through a the XTestFakeInput request.
- 8.8 High severity
Server: Buffer Copy without Checking Size of Input
A vulnerability classified as critical was found in X.org Server. Affected by this vulnerability is the function _GetCountedString of the file xkb/xkb.c. The manipulation leads to buffer overflow. It is recommended to apply a patch to fix this issue. The assoc
- 7.8 High severity
xorg-x11-server: Out-of-bounds Write
A flaw was found in the Xorg-x11-server. The specific flaw exists within the handling of ProcXkbSetDeviceInfo requests. The issue results from the lack of proper validation of user-supplied data, which can result in a memory access past the end of an allocated
- 7.8 High severity
xorg-x11-server: Improper Protection for Outbound Error Messages and Alert Signals
A flaw was found in the Xorg-x11-server. An out-of-bounds access issue can occur in the ProcXkbSetGeometry function due to improper validation of the request length.