What's the issue?
The sa login has been renamed.
Why is this a problem?
Renaming the sa login does not prevent it from being discovered, as by default any login in the public role can determine what it has been renamed to. Additionally, if you are renaming the sa login, be sure to let other administrators know to avoid confusion. Renaming the account can also cause issues with SQL Agent jobs in certain circumstances. Mostly, be aware that obscurity is not a primary form of security.
What should you do about this?
Whatever this login is named, it is more important to have it disabled to prevent it's usage by external connections. Renaming the sa login and create a "dummy" sa login is sometimes used as a "honey pot" to monitor and trap malicious login attempts, but only do this is you are intending to actively monitor and respond to these kinds of login attempts.
Vulnerability
Category
What do the Vulnerability Levels mean?
0 - Information only. This is stuff you should know about your instances like version and service account used, but if you don't know it…well, now you do.
1 - High vulnerability requiring action. These are the issues that could most likely lead to your company being front page news for all the wrong reasons. If your instances have any results at this level then we recommend cancelling that 3-martini lunch and instead huddling with your team to figure out when to address these issues.
2 - High vulnerability to review. These include settings and assigned permissions you should review soon, if not immediately. These findings may not necessarily indicate a clear vulnerability, but we've found unexpected vulnerabilities in these categories at many, many clients.
3 - Potential vulnerability to review. These are configurations or assigned permissions you may be using that could lead to problems for users. Or maybe they're just required for your applications. Either way, we recommend reviewing these to make sure these are correct.
4 – Low vulnerability with recommended action. These are typically security inconsistencies that should be addressed. They aren't likely to cause problems, but you should clean up the mess.