The WP Project Manager plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check in the 'check' method of the 'Create_Milestone', 'Create_Task_List', 'Create_Task', and 'Delete_Task' classes in version 2.6.14. This makes it possible for unauthenticated attackers to create milestones, create task lists, create tasks, or delete tasks in any project. NOTE: Version 2.6.14 implemented a partial fix for this vulnerability.