The Visitor Traffic Real Time Statistics WordPress plugin before 3.9 does not validate and escape user input passed to the today_traffic_index AJAX action (available to any authenticated users) before using it in a SQL statement, leading to an SQL injection issue
Low privileged users can use the AJAX action 'cp_plugins_do_button_job_later_callback' in the Visitor Traffic Real Time Statistics WordPress plugin before 2.12, to install any plugin (including a specific version) from the WordPress repository, as well as activate arbitrary plugin from then blog, which helps attackers install vulnerable plugins and could lead to more critical vulnerabilities like RCE.