Root access allows someone to access your machine as a "superuser" with read and write privileges to many ore system files, including those in other macOS accounts. Luckily, the fix is fairly easy. As developer Colourmeamused tweeted, you need to set a root password:

Everyone with a Mac needs to set a root password NOW.

As a user with admin access, type the following command from the Terminal.



sudo passwd -u root



Enter your password then a new password for the root user.

Anyone got a better fix?@SwiftOnSecurity @rotophonic @pwnallthethings — colourmeamused (@colourmeamused_) November 28, 2017

Engadget has confirmed that this will secure your macOS High Sierra machine, and keep people from gaining root access as above. We've reached out to Apple and will update this post when we hear back.

Update, 5:30 PM ET: Apple provided a statement to Buzzfeed, saying that a software update was forthcoming to address this issue. It also notes how to set a root password to protect your computer in the meantime.