libXfont -- Stack buffer overflow in parsing of BDF font files in libXfont

freedesktop.org reports:

A BDF font file containing a longer than expected string can cause
a buffer overflow on the stack. Testing in X servers built with
Stack Protector restulted in an immediate crash when reading a
user-proveded specially crafted font.
As libXfont is used to read user-specified font files in all X
servers distributed by X.Org, including the Xorg server which is
often run with root privileges or as setuid-root in order to access
hardware, this bug may lead to an unprivileged user acquiring root
privileges in some systems.