New Mac Exploit Easily Bypasses Gatekeeper Security, Could Allow Installation of Malicious Apps

Apple introduced Gatekeeper in 2012, creating it as a method of protection for users against malicious threats by adding various layers of security during installation of Mac apps. The feature is intended to ensure that apps users try to install on their Macs are legitimate and signed by a registered developer, minimizing the threat of malware. But now, a security researcher has discovered a simple method of bypassing Gatekeeper using a binary file already trusted by Apple to attack a user's computer (via Ars Technica).

macbook_pro_15_imac_27
Gatekeeper is meant solely to check the initial digital certificate when an app is downloaded on a Mac, ensuring that the program has been signed by an Apple-approved developer or at least comes from the Mac App Store itself before allowing the installation to proceed.

"If the application is valid—so it was signed by a developer ID or was (downloaded) from the Mac App Store—Gatekeeper basically says 'OK, I'm going to let this run,' and then Gatekeeper essentially exits," Patrick Wardle, director of research of security firm Synack, told Ars. "It doesn't monitor what that application is doing. If that application turns around and either loads or executes other content from the same directory... Gatekeeper does not examine those files."

Even if Gatekeeper is enhanced to its highest level of security settings, the new exploit can take advantage of a computer. Once the trusted file makes its way past the security program, it can then execute a handful of other malicious programs attached with the rest of the installation and gains the ability to install malicious software such as password-stealing programs, apps that can capture audio and video from a Mac's camera, and botnet software.

The researcher who discovered the exploit sent news of it to Apple about 60 days ago and "believes they are working on a way to fix the underlying cause or at least lessen the damage it can do to end users." Since then, an Apple spokesperson has confirmed the company is working on a patch for the issue and has asked that the identities of the specific files used in the exploit not be disclosed. Wardle plans to showcase his research on the Gatekeeper exploit at the Virus Bulletin Conference on Thursday in Prague.

Popular Stories

iPhone SE 4 Thumb 1

iPhone SE 4 With Apple's Own 5G Modem 'Confirmed' to Launch in March

Tuesday November 19, 2024 12:12 pm PST by
Barclays analyst Tom O'Malley and his colleagues recently traveled to Asia to meet with various electronics manufacturers and suppliers. In a research note this week, outlining key takeaways from the trip, the analysts said they have "confirmed" that a fourth-generation iPhone SE with an Apple-designed 5G modem is slated to launch towards the end of the first quarter next year. In line with previo...
airtag purple

AirTag 2 Rumored to Launch Next Year With These New Features

Sunday November 17, 2024 5:18 am PST by
Apple released the AirTag in April 2021, so it is now three over and a half years old. While the AirTag has not received any hardware updates since then, a new version of the item tracking accessory is rumored to be in development. Below, we recap rumors about a second-generation AirTag. Timing Apple is aiming to release a new AirTag in mid-2025, according to Bloomberg's Mark Gurman....
Magic Mouse Next to Keyboard

No, Apple CEO Tim Cook Didn't Say He Prefers Logitech's MX Master 3 Over the Magic Mouse

Sunday November 17, 2024 3:03 pm PST by
While the Logitech MX Master 3 is a terrific mouse for the Mac, reports claiming that Apple CEO Tim Cook prefers that mouse over the Magic Mouse are false. The Wall Street Journal last month published an interview with Cook, in which he said he uses every Apple product every day. Soon after, The Verge's Wes Davis attempted to replicate using every Apple product in a single day. During that...
Generic iOS 18 Feature Real Mock

Apple Releases iOS 18.1.1 and iPadOS 18.1.1 With Security Fixes

Tuesday November 19, 2024 10:10 am PST by
Apple today released iOS 18.1.1 and iPadOS 18.1.1, minor updates to the iOS 18 and iPadOS 18 operating systems that debuted earlier in September. iOS 18.1.1 and iPadOS 18.1.1 come three weeks after the launch of iOS 18.1. The new software can be downloaded on eligible iPhones and iPads over-the-air by going to Settings > General > Software Update. Apple has also released iOS 17.7.2 for...
at t turbo indicator iphone 16 pro max v0 8hrh7w5f3w1e1

AT&T Turbo Indicator Showing Up in iPhone Status Bar for Subscribers

Wednesday November 20, 2024 3:42 am PST by
AT&T has begun displaying "Turbo" in the iPhone carrier label for customers subscribed to its premium network prioritization service, according to reports on Reddit. The new indicator seems to have started appearing after users updated to iOS 18.1.1, but that could be just coincidence. Image credit: Reddit user No_Highlight7476 The Turbo feature provides enhanced network performance through ...
iPhone 17 Slim Feature Single Camera 1 Redux

'iPhone 17 Air' Rumored to Surpass iPhone 6 as Thinnest iPhone Ever

Monday November 18, 2024 1:07 pm PST by
In a research note with Hong Kong-based investment bank Haitong today, obtained by MacRumors, Apple analyst Jeff Pu said he agrees with a recent rumor claiming that the so-called "iPhone 17 Air" will be around 6mm thick. "We agreed with the recent chatter of an 6mm thickness ultra-slim design of the iPhone 17 Slim model," he wrote. If that measurement proves to be accurate, there would be ...
bug security vulnerability issue fix larry

Make Sure to Update: iOS 18.1.1 and macOS Sequoia 15.1.1 Fix Actively Exploited Vulnerabilities

Tuesday November 19, 2024 10:52 am PST by
The iOS 18.1.1, iPadOS 18.1.1, and macOS Sequoia 15.1.1 updates that Apple released today address JavaScriptCore and WebKit vulnerabilities that Apple says have been actively exploited on some devices. With the JavaScriptCore vulnerability, processing maliciously crafted web content could lead to arbitrary code execution. The WebKit vulnerability had the same issue with maliciously crafted...

Top Rated Comments

Codyak Avatar
119 months ago
-Gategate
Score: 20 Votes (Like | Disagree)
cariacou Avatar
119 months ago
Your Mac has either a 14nm Samsung CPU or a 16nm TSMC CPU.

To check which one you have, please click on this link...
Score: 13 Votes (Like | Disagree)
DavidTheExpert Avatar
119 months ago
There's a very simple way to avoid malware on any computer: Don't install anything you don't trust.
Score: 6 Votes (Like | Disagree)
garylapointe Avatar
119 months ago
I tend to assume that there are ways around all forms of security protection.
But the app store has always made me feel a little safer...

Gary
Score: 4 Votes (Like | Disagree)
Lord Hamsa Avatar
119 months ago
I'm not particularly concerned about this "exploit". Anyone seeking to make use of it could just as easily put the malware directly in the developer-signed application in the first place. Why go through the extra steps of invoking additional applications when you can do it in the initial one?

The only thing that keeps the self-signed applications on the up-and-up is that the developer ID can be revoked for bad behavior - whether it's in the signed application or a bundled application called by it makes little difference if the developer is doing this intentionally.

The only real attack vector here is if an application is known to invoke "helper" executables, and someone executes a man-in-the-middle attack to create a modified distribution with the legit signed main application but with one or malware-infected helper executables, and then pass that off as a legit bundle. Possible, but limiting downloads to trusted/official sites will prevent that.
Score: 4 Votes (Like | Disagree)
JimmyHook Avatar
119 months ago
This is an old one. The "fix" is to download software from trusted sources only. Which is what you should do anyway. The guy even said it isn't a bug, it's a limitation in gatekeeper.
Score: 3 Votes (Like | Disagree)