The form API in Drupal 6.x before 6.29 and 7.x before 7.24, when used with unspecified third-party modules, performs form validation even when CSRF validation has failed, which might allow remote attackers to trigger application-specific impacts such as arbitrary code execution via application-specific vectors.
https://drupal.org/SA-CORE-2013-003
http://www.openwall.com/lists/oss-security/2013/11/22/4
http://www.debian.org/security/2013/dsa-2828