The get_poll_categories(), get_polls() and get_reports() functions in the Poll Maker WordPress plugin before 3.2.1 did not use whitelist or validate the orderby parameter before using it in SQL statements passed to the get_results() DB calls, leading to SQL injection issues in the admin dashboard
https://wpscan.com/vulnerability/0dc931c6-1fce-4d70-a658-a4bbab10dab3