The WP Component WordPress plugin through 2.2.4 does not have any capability or nonce checks on one of the actions it makes available to unauthenticated users, and it takes both the option name and the option value from the request, allowing unauthenticated attackers to overwrite any of the site's options. On a single site installation this leads to a full takeover, as registration can be enabled with a default role of administrator.
Credits
Enrico Marcolini - Claudio Marchesini - Dottor Marc
