Note: This is an archival copy of Security Sun Alert 228524 as previously published on http://sunsolve.sun.com.|
Latest version of this security advisory is available from http://support.oracle.com as Sun Alert 1017426.1.
Solaris 9 Operating System
Solaris 10 Operating System
Solaris 8 Operating System
Date of Workaround Release
Date of Resolved Release
The Xsun(1) server and Xorg(1) server are the X display servers for Version 11 of the X window system on Solaris.
There exists an overflow vulnerability when performing integer multiplication within the libXfont library, as used by the X11 display servers, that can cause a heap overflow while loading the fonts. This may allow a local unprivileged user to be able to execute arbitrary commands with elevated privileges or create a Denial of Service (DoS) to the display managers.
This issue is described in the following documents:
This issue can occur in the following releases:
Note: Xorg(1) is not shipped in Solaris 8
To determine the version of JDS that is currently installed on the system, run the following command (output will vary by platform):
% grep platform /usr/share/gnome/gnome-about/gnome-version.xml <platform>2</platform>
Alternatively (for the same results), in a terminal window from within the GNOME desktop, the following command can be run:
There are no predictable symptoms that would indicate that this issue has been exploited to execute arbitrary commands with elevated privileges. The symptom of the Denial of Service (DoS) would be the absence of either the Xsun(1) or Xorg(1) server running on the system.
To prevent this issue from being exploited to execute arbitrary commands with elevated privileges, the setuid(2) bit can be removed from the Xorg server and the Xsun server on the x86 platform and the setgid(2) bit can be removed from the Xsun server on the SPARC platform. For example:
# chmod 0755 /usr/openwin/bin/Xsun # chmod 0755 /usr/X11/bin/Xorg
Note 1: Performing the above procedure will disable the following:
These features will still be available to Xsun and Xorg when started via a display manager such as dtlogin(1), gdm(1), or xdm(1).
Note 2: There is no workaround to prevent this issue from being exploited to cause a Denial Of Service to the X Servers.
Note 3: The "chmod" command for Xorg(1) is applicable only to Solaris 9 and 10.
Note 4: Local users on the console of a system using an X display manager and Sun Ray users may still be able to exploit this vulnerability to execute arbitrary commands with elevated privileges even if the setuid and setgid permissions have been removed from the Xsun and Xorg binaries.
This issue is addressed in the following releases:
This solution has no attachment