Log file viewer not displaying database where error occurred

Question

Something keeps being logged to files located here:

C:\Program Files\Microsoft SQL Server\MSSQL11.SQLSERVER\MSSQL\Log

Files like these keep getting updated: SQLFT0000700007.LOG

15 errors per second! Obviously, the server ran out of disk space!

The errors are always the same and keep happening:

"Login failed for 'aspnet' user. Reason: Could not find a login matching the name provided."

And alternates with:

"Error: 18456, Severity:14, State: 5."

Why can't I see the database with which it is associated? Or wherever the request is coming from?

And how do I find the cause of this issue?

Answer 1

You can't see the database because a login is a server/instance-level object. Users are database-level objects. It's also possible the attacker was trying to brute-force the aspnet login without specifying an initial database, in hopes that it is already mapped to a user and a default database.

Answer 2

This was a brute force attack on my SQL Server. I used the firewall settings to block requests from the IP specified at the end of the message (not displayed in the question).