CVE-2017-13721
In X.Org Server (aka xserver and xorg-server) before 1.19.4, an attacker authenticated to an X server with the X shared memory extension enabled can cause aborts of the X server or replace shared memory segments of other X clients in the same session.
Date published : 2017-10-09
http://www.securityfocus.com/bid/101238
https://cgit.freedesktop.org/xorg/xserver/commit/?id=b95f25af141d33a65f6f821ea9c003f66a01e1f1