A security issue affects the following Ubuntu releases:
Ubuntu 4.10 (Warty Warthog)
The following packages are affected:
The problem can be corrected by upgrading the affected package to version 0.22-1ubuntu2.1. You have to restart your Gnome session (i.e. log out and back in) after doing a standard system upgrade to effect the necessary changes.
Besides providing the global system-wide communication bus, dbus also offers per-user "session" buses which applications in an user's session can create and use to communicate with each other. Daniel Reed discovered that the default configuration of the session dbus allowed a local user to connect to another user's session bus if its address was known. The fixed packages restrict the default permissions to the user who owns the session dbus instance.
Please note that a standard Ubuntu installation does not use the session bus for anything, so this can only be exploited if you are using custom software which uses it.