pam_ssh 1.92 and possibly other versions, as used when PAM is compiled with USE=ssh, generates different error messages depending on whether the username is valid or invalid, which makes it easier for remote attackers to enumerate usernames.Referenceshttp://bugs.gentoo.org/show_bug.cgi?id=263579http://secunia.com/advisories/34986http://secunia.com/advisories/34536https://www.redhat.com/archives/fedora-package-announce/2009-May/msg00116.htmlhttps://www.redhat.com/archives/fedora-package-announce/2009-May/msg00145.html
