Description
mod/data/edit.php in Moodle through 2.4.11, 2.5.x before 2.5.9, 2.6.x before 2.6.6, and 2.7.x before 2.7.3 sets a certain group ID to zero upon a database-entry change, which allows remote authenticated users to obtain sensitive information by accessing the database after an edit by a teacher.