I have to ask everyone on this site to change his password immediately, for which I am quite sorry.
The site's software has had a critical security issue, which was fixed very fast, and the site updated to the new version as fast as possible.
Still I cannot promise that the site did not get hacked, and the worst thing is, that it is not possible to detect either.
This is the first time in many years that something this severe happened, the software is known to be very secure and stable and is broadly used by many big sites.
More information can be found at https://www.drupal.org/SA-CORE-2014-005