X.Org X Server vulnerabilities

98 vulnerabilities

Known vulnerabilities in X.Org X Server, newest first, with CVSS severity, EPSS, KEV listings, ransomware use and the affected versions.

7.2CVE-2018-14665alpinexorg-server+33
EPSS score
27.04%
A flaw was found in xorg-x11-server before 1.20.3. An incorrect permission check for -modulepath and -logfile options when starting Xorg. X server allows unprivileged users with the ability to log in to the system via physical console to escalate their privileges and run arbitrary code under root privileges.
7.8CVE-2021-4010debianxorg-server+7
EPSS score
0.61%
A flaw was found in xorg-x11-server in versions before 21.1.2 and before 1.20.14. An out-of-bounds access can occur in the SProcScreenSaverSuspend function. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
7.8CVE-2021-4008debianxorg-server+42
EPSS score
0.61%
A flaw was found in xorg-x11-server in versions before 21.1.2 and before 1.20.14. An out-of-bounds access can occur in the SProcRenderCompositeGlyphs function. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
7.8CVE-2021-4009debianxorg-server+8
EPSS score
0.61%
A flaw was found in xorg-x11-server in versions before 21.1.2 and before 1.20.14. An out-of-bounds access can occur in the SProcXFixesCreatePointerBarrier function. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
7.8CVE-2021-4011debianxorg-server+10
EPSS score
0.61%
A flaw was found in xorg-x11-server in versions before 21.1.2 and before 1.20.14. An out-of-bounds access can occur in the SwapCreateRegister function. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
7.8CVE-2021-3472alpinexorg-server+55
EPSS score
1.05%
A flaw was found in xorg-x11-server in versions before 1.20.11. An integer underflow can occur in xserver which can lead to a local privilege escalation. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.
6.4CVE-2015-0255debianxorg-server+27
EPSS score
4.50%
X.Org Server (aka xserver and xorg-server) before 1.16.3 and 1.17.x before 1.17.1 allows remote attackers to obtain sensitive information from process memory or cause a denial of service (crash) via a crafted string length value in a XkbSetGeometry request.
3.6CVE-2015-3164debianxorg-server+5
EPSS score
0.39%
The authentication setup in XWayland 1.16.x and 1.17.x before 1.17.2 starts the server in non-authenticating mode, which allows local users to read from or send information to arbitrary X11 clients via vectors involving a UNIX socket.
7.5CVE-2015-3418debianxorg-server+13
EPSS score
2.31%
The ProcPutImage function in dix/dispatch.c in X.Org Server (aka xserver and xorg-server) before 1.16.4 allows attackers to cause a denial of service (divide-by-zero and crash) via a zero-height PutImage request.
9.3CVE-2007-6427applemac_os_x+11
EPSS score
4.28%
The XInput extension in X.Org Xserver before 1.4.1 allows context-dependent attackers to execute arbitrary code via requests related to byte swapping and heap corruption within multiple functions, a different vulnerability than CVE-2007-4990.
7.3CVE-2025-62231debianxorg-server+16
EPSS score
0.30%
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.
7.3CVE-2025-62230debianxorg-server+16
EPSS score
0.28%
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.
7.8CVE-2025-26600debianxorg-server+9
EPSS score
0.39%
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.
7.8CVE-2025-26597debianxorg-server+34
EPSS score
0.44%
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.
7.8CVE-2025-26594debianxorg-server+9
EPSS score
0.39%
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.
7.8CVE-2025-26599debianxorg-server+9
EPSS score
0.40%
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.
7.8CVE-2025-26598debianxorg-server+9
EPSS score
0.40%
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.
7.8CVE-2025-26595debianxorg-server+28
EPSS score
0.44%
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.
7.8CVE-2025-26596debianxorg-server+9
EPSS score
0.44%
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.
7.8CVE-2025-26601debianxorg-server+9
EPSS score
0.39%
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.