The rsaauth extension in TYPO3 4.3.0 through 4.3.14, 4.4.0 through 4.4.15, 4.5.0 through 4.5.39, and 4.6.0 through 4.6.18, when configured for the frontend, allows remote attackers to bypass authentication via a password that is casted to an empty value.
https://review.typo3.org/#/c/37013/
http://www.securitytracker.com/id/1031824
http://www.securityfocus.com/bid/72763
http://www.openwall.com/lists/oss-security/2015/02/22/8
http://www.openwall.com/lists/oss-security/2015/02/22/4
http://www.debian.org/security/2015/dsa-3164
http://typo3.org/teams/security/security-bulletins/typo3-core/typo3-core-sa-2015-001/
http://lists.opensuse.org/opensuse-updates/2016-08/msg00106.html