The pam_sm_close_session function in pam_xauth.c in the pam_xauth module in Linux-PAM (aka pam) 1.1.2 and earlier does not properly handle a failure to determine a certain target uid, which might allow local users to delete unintended files by executing a program that relies on the pam_xauth PAM check.
https://exchange.xforce.ibmcloud.com/vulnerabilities/65035
http://www.securityfocus.com/bid/46045
http://security.gentoo.org/glsa/glsa-201206-31.xml
http://secunia.com/advisories/49711