Open redirect vulnerability in URL-related API functions in Drupal 6.x before 6.35 and 7.x before 7.35 allows remote attackers to redirect users to arbitrary web sites and conduct phishing attacks via vectors involving the “//” initial sequence.
cgit.drupalcode.org/drupal/commit/includes/common.inc?h=7.x&id=b44056d2f8e8c71d35c85ec5c2fb8f7c8a02d8a8
cgit.drupalcode.org/drupal/commit/includes/menu.inc?h=6.x&id=8ffc5db3c0ab926f3d4b2cf8bc51714c8c0f3c93
www.debian.org/security/2015/dsa-3200
www.openwall.com/lists/oss-security/2015/03/26/4
www.securityfocus.com/bid/73219
www.drupal.org/SA-CORE-2015-001