MEDIUM
Linux-PAM before 1.0.4 does not enforce the minimum password age (MINDAYS) as specified in /etc/shadow, which allows local users to bypass intended security policy and change their passwords sooner than specified.
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=514437
http://secunia.com/advisories/34728
http://secunia.com/advisories/34733
https://bugzilla.redhat.com/show_bug.cgi?id=487216
https://www.redhat.com/archives/fedora-package-announce/2009-April/msg00398.html
https://www.redhat.com/archives/fedora-package-announce/2009-April/msg00420.html
https://www.redhat.com/archives/pam-list/2009-March/msg00006.html