TeamPass before 2.1.20 allows remote attackers to bypass access restrictions via a request to index.php followed by a direct request to a file that calls the session_start function before checking the CPM key, as demonstrated by a request to sources/upload/upload.files.php.
https://github.com/nilsteampassnet/TeamPass/commit/7715512f2bd5659cc69e063a1c513c19e384340f
https://euvd.enisa.europa.eu/vulnerability/EUVD-2014-3711
http://www.openwall.com/lists/oss-security/2014/05/19/5