X.Org X Window System (aka X11 and X) X11R5 and X.Org Server (aka xserver and xorg-server) before 1.16.3, when using SUN-DES-1 (Secure RPC) authentication credentials, does not check the return value of a malloc call, which allows remote attackers to cause a denial of service (NULL pointer dereference and server crash) via a crafted connection request.<a href=http://cwe.mitre.org/data/definitions/476.html>CWE-476: NULL Pointer Dereference</a> http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2014-8091