Updated dbus packages that fix a security issue are now available for Red Hat Enterprise Linux 4. This update has been rated as having low security impact by the Red Hat Security Response Team.
D-BUS is a system for sending messages between applications. It is used both for the systemwide message bus service, and as a per-user-login-session messaging facility. Dan Reed discovered that a user can send and listen to messages on another user's per-user session bus if they know the address of the socket. The Common Vulnerabilities and Exposures project (cve.mitre.org) has assigned the name CAN-2005-0201 to this issue. In Red Hat Enterprise Linux 4, the per-user session bus is only used for printing notifications, therefore this issue would only allow a local user to examine or send additional print notification messages. Users of dbus are advised to upgrade to these updated packages, which contain backported patches to correct this issue.