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.
git.altlinux.org/people/ldv/packages/?p=pam.git%3Ba=commit%3Bh=Linux-PAM-1_1_2-3-g05dafc06cd3dfeb7c4b24942e4e1ae33ff75a123
openwall.com/lists/oss-security/2010/10/03/1
secunia.com/advisories/49711
security.gentoo.org/glsa/glsa-201206-31.xml
www.securityfocus.com/bid/46045
exchange.xforce.ibmcloud.com/vulnerabilities/65035