Well. As mentioned in the title, the new release of mac OSX has a massive security vulnerability, by default, and across all versions of “high sierra” (this includes developer versions) Anyone who sits down in front of a machine with the new OS can gain root access by simply leaving the passwod blank. (assuming the user has not thought to set a root password, which is likely exceedingly common.)   As of now, there is no official word on when a patch will be issued for those who are unwilling or unable to follow the procedure to remedy the issue.   Setting a secure root password and disabling guest access is the current fix.   Disabling guest user on macOS High Sierra Step 1 | Launch System Preferences Step 2 | Select Users & Groups Step 3 | Select Guest User Step 4 | Uncheck Allow guests to log in to this computer   Changing root password on macOS High Sierra Step 1 | Launch System Preferences Step 2 | Select Users & Groups Step 3 | Select Login Options Step 4 | Select Join next to Network Account Server Step 5 | Select Open Directory Utility Step 6 | Click the lock and enter your password to make changes Step 7 | In the menu bar of Directory Utility, select Change Root Password Step 8 | Create a strong, unique password     Also, an open letter to software developers: Please, for crying out loud, test things before you release them. Thank you. -Tom Lidikay Edit 11/29/17:  Apple has released a security patch to fix this, if you have not already, go update your machine NOW.