Integer overflow in the ProcDRI2GetBuffers function in the DRI2 extension in X.Org Server (aka xserver and xorg-server) 1.7.0 through 1.16.x before 1.16.3 allows remote authenticated users to cause a denial of service (crash) or possibly execute arbitrary code via a crafted request, which triggers an out-of-bounds read or write.

The X.Org X wrapper (xserver-wrapper.c) in Debian GNU/Linux and Ubuntu Linux does not properly verify the TTY of a user who is starting X, which allows local users to bypass intended access restrictions by associating stdin with a file that is misinterpreted as the console TTY.

Buffer overflow in X.org libXv 1.0.7 and earlier allows X servers to cause a denial of service (crash) and possibly execute arbitrary code via crafted length or index values to the XvQueryPortAttributes function.

Multiple buffer overflows in X.org libXi 1.7.1 and earlier allow X servers to cause a denial of service (crash) and possibly execute arbitrary code via crafted length or index values to the (1) XGetDeviceButtonMapping, (2) XIPassiveGrabDevice, and (3) XQueryDeviceState functions.

X.org libXi 1.7.1 and earlier allows X servers to trigger allocation of insufficient memory and a buffer overflow via vectors related to an unexpected sign extension in the XListInputDevices function.

Multiple integer overflows in X.org libXi 1.7.1 and earlier allow X servers to trigger allocation of insufficient memory and a buffer overflow via vectors related to the (1) XGetDeviceControl, (2) XGetFeedbackControl, (3) XGetDeviceDontPropagateList, (4) XGetDeviceMotionEvents, (5) XIGetProperty, (6) XIGetSelectedEvents, (7) XGetDeviceProperties, and (8) XListInputDevices functions.

The GLX extension in X.Org xserver 1.7.7 allows remote authenticated users to cause a denial of service (server crash) and possibly execute arbitrary code via (1) a crafted request that triggers a client swap in glx/glxcmdsswap.c; or (2) a crafted length or (3) a negative value in the screen field in a request to glx/glxcmds.c.

The LockServer function in os/utils.c in X.Org xserver before 1.11.2 allows local users to change the permissions of arbitrary files to 444, read those files, and possibly cause a denial of service (removed execution permission) via a symlink attack on a temporary lock file.

The LockServer function in os/utils.c in X.Org xserver before 1.11.2 allows local users to determine the existence of arbitrary files via a symlink attack on a temporary lock file, which is handled differently if the file exists.

Format string vulnerability in the LogVHdrMessageVerb function in os/log.c in X.Org X11 1.11 allows attackers to cause a denial of service or possibly execute arbitrary code via format string specifiers in an input device name.