X.Org X Server: Privilege escalation

Background

The X Window System is a graphical windowing system based on a client/server model.

Description

The “LogVHdrMessageVerb()” function in log.c contains a format string vulnerability.

NOTE: Exposure to this vulnerability is reduced in Gentoo due to X.Org X Server being built with “-D_FORTIFY_SOURCE=2” by default.

Impact

A local attacker could gain escalated privileges or cause a Denial of Service condition.

Workaround

There is no known workaround at this time.

Resolution

All X.Org X Server 1.11.x users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=x11-base/xorg-server-1.11.4-r1"

All X.Org X Server 1.10.x users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=x11-base/xorg-server-1.10.6-r1"

X.Org X Server 1.9.x is not affected.