Half of a client's Drupal 7 sites were compromised over the weekend.
If you did not update your Drupal 7 website by about Friday, your site was probably hacked too: Update to Drupal 7.32 or apply the patch manually updating is not trivial.
After that, you will need to review your site's administrator users, permissions, logs and content for unexpected users, roles, permissions, content and and scripts.
Follow or join the conversation in #drupalsa05 for more detail about known exploits and how to repair your hacked site.