If you notice the process MRT in Activity Monitor consumes a large amount of memory or an abnormally high percentage of CPU, chances are, your Mac may slow down or make a loud fan noise. The next time you see a potential threat reported from anti-malware software, you can double-check with the free Etrecheck or Malwarebytes.
Like, some third-party software like Trend Micro HouseCall for Mac may flag osx ref.9eae4e3av as a threat, though it's just MRT - the malware defence program that comes with your system. It's also not recommended to delete and since it may affect your Mac's security. If that also happens to you, ignore the notification. Some anti-virus software like Webroot may mistake the file as a suspicious activity because it makes changes to the system.
If you want to check the latest update to MRT on your Mac, open the Apple menu > About This Mac > System Report, find the Installation tab under the Software section and look for MRTConfigData.Ĭom. is a legitimate settings file for MRT on Mac that you can find in the following directory: To make sure MRT is automatically updated, ensure that the "Automatically Check for Updates" and "Install system data files and security updates" are enabled in System Preferences > Software Update > Advanced. Usually, MRT is silently updated in the background so you won't receive any notification for its update.
If you right-click on the MRT app and select Show Package Contents > Contents > MacOS, you will find two Unix Executable Files named MRT and mrt-helper that run in Terminal when you double-click on them. You can access MRT by navigating to Macintosh HD/Library/Apple/System/Library/CoreServices/MRT. It examines your Mac for malware when restarting and logging in. MRT, standing for Malware Removal Tool, is a malware protection technology that automatically removes harmful software from your Mac based on the information updated by Apple.
Now, let's take a closer look at the MRT process on Mac.