Security Growler is intended to keep your computer safe. This tool monitors security events, including SSH, FTP, VNC, AFP, MySQL, PostgreSQL, iTunes Sharing and sudo auth. This way, you get convenient notifications that allow you to take appropriate actions and avoid hacking attacks.
The application is quite unobtrusive and runs from the Menu Bar, from which you can access a simple menu. There you can view a list of the sources the app is monitoring as well as of latest events. In addition, you will be alerted via the Notifications Center whenever your ports are scanned, the sudo command is used or a new connection is detected. Likewise, it keeps a log of all events, which you can consult when it becomes necessary.
It is also possible to adjust the app’s settings. However, this requires editing a Python file, which may be difficult for inexperienced users. In this regard, I wish I were easier to create a whitelist to avoid being bothered by unnecessary notifications.
All in all, Security Growler requires very little of your resources and screen space to notify you about possible security breaches. There are two versions of the tool, Security Growler (standard) with a dark interface theme and Security Growler Light, with a light theme. Please, be aware that is not actually a different app. Luckily, the tool is opensource and absolutely free to use.