For the first time ever, I’m actually grateful that I’ve been a procrastinator for most of my life, and that I may have just saved myself some major headaches simply because I’ve been putting off the suggested MacOS High Sierra update on my Mac for several months. I don’t even want to get into the problems I’ve been having with my iPhone 7, ever since I completed the suggested update. Maybe there’s a lesson to be learned here? Perhaps the next time Apple comes out with a new update, we should take our time, and see what happens to the other guy, before we click on that update button.
According to WIRED – THERE ARE HACKABLE security flaws in software. And then there are those that don’t even require hacking at all—just a knock on the door and asking to be let in. Apple’s macOS High Sierra has the second kind.
On Tuesday, security researchers disclosed a bug that allows anyone a blindingly easy method of breaking that operating system’s security protections. Anyone who hits a prompt in High Sierra asking for a username and password before logging into a machine with multiple users, they can simply type “root” as a username, leave the password field blank, click “unlock” twice, and immediately gain full access.
In other words, the bug allows any rogue user that gets the slightest foothold on a target computer to gain the deepest level of access to a computer, known as “root” privileges. Malware designed to exploit the trick could also fully install itself deep within the computer, no password required.
“We always see malware trying to escalate privileges and get root access,” says Patrick Wardle, a security researcher with Synack. “This is best, easiest way ever to get root, and Apple has handed it to them on a silver platter.”
As word of the security vulnerability rippled across Twitter and other social media, a few security researchers found they couldn’t replicate the issue, but others captured and posted video demonstrations of the attack, like Wardle’s GIF below, and another that shows security researcher Amit Serper logging into a logged-out account. WIRED also independently confirmed the bug.
Watch these two incredible videos posted to Twitter letting Apple know they have a “HUGE” security issue at MacOS High Sierra:
— patrick wardle (@patrickwardle) November 28, 2017
Just tested the apple root login bug. You can log in as root even after the machi was rebooted pic.twitter.com/fTHZ7nkcUp
— Amit Serper (@0xAmit) November 28, 2017
The fact that the attack could be used on a logged-out account raises the possibility that someone with physical access could exploit it just as easily as malware, points out Thomas Reed, an Apple-focused security researcher with MalwareBytes. They could, for instance, use the attack to gain root access to a logged-out machine, set a root password, and then regain access to a machine at any time. “Oooh, boy, this is a doozy,” says Reed. “So, if someone did this to a Mac sitting on a desk in an office, they could come back later and do whatever they wanted.”
Facebook user Brian Matiash tells Mac users about how they protect their Mac from being hacked. We cannot confirm or deny if his advice is legit, we are simply sharing it with you. Matiash gives Facebook users the following advice: Wonders never cease, Apple. How can such a painfully obvious bug like this make it by your QA teams? At least make the default root password be ‘password’ or something. FFS, guys. Get you damned act together.
EDIT: It would be socially responsible of me to state that there is a fairly easy workaround. Start by opening up Terminal.app and type the following command:
sudo passwd -u root
Next, enter your primary user password. Then, enter a new password for root and retype it to confirm. There. You’re protected.
Reed also notes, however—and other researchers confirm—that it’s possible to block the attack by either setting a password for the root user or disabling root access altogether. If you’ve installed High Sierra and haven’t set a root password or disabled root access, you should do it now.
In a statement, Apple confirmed the problem, reiterated that short-term fix, and promised a longer-term software patch: “We are working on a software update to address this issue,” an Apple spokesperson wrote.