On Tuesday, a macOS 10.13.1 security issue was revealed—a flaw that allows root access to a Mac without the need for a password. Developer Lemi Orhan Ergin tweeted that anyone can log into a Mac by entering the user name
root without a password. The first time you try to login, it won’t work. But if you try it again, you will be granted access. Here’s Erign’s tweet:
Dear @AppleSupport, we noticed a HUGE security issue at MacOS High Sierra. Anyone can login as “root” with empty password after clicking on login button several times. Are you aware of it @Apple?
— Lemi Orhan Ergin (@lemiorhan) November 28, 2017
At Macworld, we tried it on our own MacBook Pro running macOS 10.13.1, and the root login worked. See the video below.
This issue seemed to work only after you are logged into a Mac under a different user name. I wasn’t able to use
root and no password at the Mac’s user login screen that appears at startup.
Apple was contacted for a comment, but had not responded to us as of this posting. We will update this article if we hear from the company.
As Apple’s support document notes,
root is a “superuser” that grants access to areas of the system that are often used by system administrators.
How to fix the root security issue
This hole will probably be fixed in a future macOS High Sierra update. In the meantime, there are steps users can take to fix the hole. The fix is to change the password for
root. Here’s how.
1. In the Finder, click on the Go menu and select Go to Folder.
2. Enter the following:
/System/Library/CoreServices/Applications/ and then click Go.
3. Find the Directory Utility app and launch it.
4. Click the lock in the lower left to make changes. In the pop-up window, enter your user name and password, then click Modify Configuration.
5. Click on Edit in the menu bar and select Change Root Password.
6. In the pop-up window, enter a password and verify it. Click OK.
7. In the main window of Directory Utility, click the lock to lock it and prevent further changes.
8. Quit Directory Utility. You are done.
If you try to enter
root without a password at a login prompt, the promt will shake and reject your login. You’ll need to enter your new password to gain