auth_login.php in Cacti before 0.8.8g allows remote authenticated users who use web authentication to bypass intended access restrictions by logging in as a user not in the cacti database.
https://security.gentoo.org/glsa/201711-10
https://security.gentoo.org/glsa/201607-05
http://www.securitytracker.com/id/1037745
http://www.cacti.net/release_notes_0_8_8g.php
http://lists.opensuse.org/opensuse-updates/2016-02/msg00080.html
http://lists.opensuse.org/opensuse-updates/2016-02/msg00078.html
http://lists.opensuse.org/opensuse-updates/2016-02/msg00077.html