CVE-2015-0255

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.

CVE-2015-3164

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.