lightdm before 1.0.9 does not properly close file descriptors before opening a child process, which allows local users to write to the lightdm log or have other unspecified impact.
https://euvd.enisa.europa.eu/vulnerability/EUVD-2012-1145
https://bugzilla.novell.com/show_bug.cgi?id=745339
https://bugs.launchpad.net/ubuntu/+source/lightdm/+bug/927060
http://seclists.org/oss-sec/2012/q1/566
http://seclists.org/oss-sec/2012/q1/557
http://lists.opensuse.org/opensuse-updates/2012-03/msg00019.html