Default credentials

tiki-login.php in Tiki before 21.2 sets the admin password to a blank value after 50 invalid login attempts...

CVE-2012-5522: Undefined Security Weakness

MantisBT before 1.2.12 does not use an expected default value during decisions about whether a user may modify the status of a bug, which allows remote authenticated users to bypass intended access restrictions and make status changes by leveraging a blank value for a per-status setting...