LibXfont, TightVNC: Multiple vulnerabilities

Background

LibXfont is the X.Org font library. TightVNC is a VNC client/server for X displays.

Description

The libXfont code is prone to several integer overflows, in functions ProcXCMiscGetXIDList(), bdfReadCharacters() and FontFileInitTable(). TightVNC contains a local copy of this code and is also affected.

Impact

A local attacker could use a specially crafted BDF Font to gain root privileges on the vulnerable host.

Workaround

There is no known workaround at this time.

Resolution

All libXfont users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=x11-libs/libXfont-1.2.7-r1"

All TightVNC users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=net-misc/tightvnc-1.2.9-r4"