Enable Media Replace WordPress Plugin
A user can perform SQL Injection attacks against the plugin at the Replace Media Upload page (Media > Edit > Upload a new file). By changing the 'attachment_id' parameter in the URL to 'attachment_id=99999+union+select+concat(0x20,user_login),+user_pass+from+wp_users+where+ID=1', the plugin will retrieve and display the administrator's user name and password hash. This requires that the attacker has knowledge of the SQL table prefix, but that can be retrieved as well from information_schema.TABLES. A user can also upload arbitrary files, including PHP files, at the Replace Media Upload page using the 'Replace the file' functionality, which doesn't check if uploaded files have an allowed extension. This can be exploited to execute arbitrary PHP code and for instance retrieve or change sensitive information in the SQL database or the web server's file system.