no security event logs for brute force attacks

There is a separate event log for Brute Force specifically. Did you already look in Security > Event Logs > Brute Force Attacks. I assume you did and if you have the next step would be to analyze your logging profile as well as double checking that you have the correct logging profile applied to your virtual server.

Hope this helps. If you need further assistance feel free to post a picture of your logging profile in here and I can take a look at it.