An information disclosure flaw was found in the way X.org X11 server, an open source X Window System server implementation, used to register new hot-plug devices, when X.org X11 server was instructed (for that particular moment) not to receive input devices events. Formerly when registering new input device, X.org X11 server simultaneously enabled retrieval of input from the particular device (regardless of the setting). A local unsuspecting user, relying on the X.org X11 server disable input feature it to properly prohibit acquiring of events from this newly added hot-plug device, could supply a sensitive information that, due the above bug, would become available to the physically proximate attackers.
Acknowledgements: This issue was found by David Airlie and Peter Hutterer of Red Hat.
This issue did NOT affect the version of the xorg-x11-server package, as shipped with Red Hat Enterprise Linux 5. -- This issue affects the version of the xorg-x11-server package, as shipped with Red Hat Enterprise Linux 6.
This issue affects the versions of the xorg-x11-server package, as shipped with Fedora release of 17 and 18.
Upstream bug: https://bugs.freedesktop.org/show_bug.cgi?id=63353
Created attachment 733595 [details] Upstream patch
This issue has been classified as low impact because of the following reason(s): In order to exploit this issue, the attacker needs to - have an account on the target machine, or otherwise be able to start an app listening for key events. - have physical access to the machine to hotplug the keyboard or some other device. - be logged in at the time, but vt-switch away without the screen lock being activated. - In order to capture passwords etc, the other-use needs to have a short enough password or the other user doesn't do anything else, otherwise the events will overrun the buffer and you only get a fraction of them
Created xorg-x11-server tracking bugs for this issue Affects: fedora-all [bug 952949]
Upstream patch: http://cgit.freedesktop.org/xorg/xserver/commit/?id=6ca03b9161d33b1d2b55a3a1a913cf88deb2343f
xorg-x11-server-1.13.3-3.fc18 has been pushed to the Fedora 18 stable repository. If problems still persist, please make note of it in this bug report.
xorg-x11-server-1.14.0-6.fc19 has been pushed to the Fedora 19 stable repository. If problems still persist, please make note of it in this bug report.
Related blog posts: http://who-t.blogspot.cz/2013/04/cve-2013-1940-vt-switched-servers.html https://plus.google.com/104877287288155269055/posts/YqUmH95LTkh
xorg-x11-server-1.12.4-7.fc17 has been pushed to the Fedora 17 stable repository. If problems still persist, please make note of it in this bug report.
This issue has been addressed in following products: Red Hat Enterprise Linux 6 Via RHSA-2013:1620 https://rhn.redhat.com/errata/RHSA-2013-1620.html
Statement: (none)